00100 - Statement - CONSOLIDATED BALANCE SHEETS
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00200 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
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00400 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS
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40105 - Disclosure - Description of the business and recent developments: Basic and diluted net (loss) income per common share (Details)
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40201 - Disclosure - Property and equipment: Property and equipment, Table (Details)
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40301 - Disclosure - Accrued and other liabilities: (Details)
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40405 - Disclosure - Long-term debt: Convertible senior notes (Details)
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40406 - Disclosure - Long-term debt: Long-term debt maturities (Details)
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40501 - Disclosure - Income taxes: Components of (loss) income before income taxes (Details)
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40502 - Disclosure - Income taxes: Temporary differences comprising our net deferred tax assets (Details)
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40506 - Disclosure - Income taxes: Effective Income Tax Rate Reconciliation (Details)
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40602 - Disclosure - Commitments and contingencies: Future minimum payments under capital lease agreements (Details)
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40603 - Disclosure - Commitments and contingencies: Future minimum payments under capital lease agreements, continued (Details)
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40606 - Disclosure - Commitments and contingencies: Future minimum annual payments under operating lease arrangements (Details)
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00090 - Document - Document and Entity Information
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00105 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical)
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00205 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical)
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00300 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY
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00405 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS
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10101 - Disclosure - Description of the business and summary of significant accounting policies:
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10201 - Disclosure - Property and equipment:
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10301 - Disclosure - Accrued and other liabilities:
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10401 - Disclosure - Long-term debt:
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10501 - Disclosure - Income taxes:
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10601 - Disclosure - Commitments and contingencies:
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10701 - Disclosure - Stockholders' equity:
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10801 - Disclosure - Stock option and award plan:
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10901 - Disclosure - Related party transactions:
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11001 - Disclosure - Geographic information:
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11101 - Disclosure - Quarterly financial information (unaudited):
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11201 - Disclosure - Subsequent Events:
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11301 - Disclosure - Schedule II VALUATION AND QUALIFYING ACCOUNTS
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20102 - Disclosure - Description of the business and summary of significant accounting policies: (Policies)
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30103 - Disclosure - Description of the business and summary of significant accounting policies: (Tables)
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30203 - Disclosure - Property and equipment: (Tables)
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30303 - Disclosure - Accrued and other liabilities: (Tables)
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30403 - Disclosure - Long-term debt: (Tables)
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30503 - Disclosure - Income taxes: (Tables)
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30603 - Disclosure - Commitments and contingencies: (Tables)
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30703 - Disclosure - Stockholders' equity: (Tables)
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30803 - Disclosure - Stock option and award plan: (Tables)
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31003 - Disclosure - Geographic information: (Tables)
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31103 - Disclosure - Quarterly financial information (unaudited): (Tables)
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40101 - Disclosure - Description of the business and summary of significant accounting policies: (Details)
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40102 - Disclosure - Description of the business and recent developments: Financial Instruments (Details)
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40103 - Disclosure - Description of the business and recent developments: Property, Plant and Equipment (Details)
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40104 - Disclosure - Description of the business and recent developments: Number of shares yield after conversion (Details)
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40106 - Disclosure - Description of the business and recent developments: Recent accounting pronouncements (Details)
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40202 - Disclosure - Property and equipment: Property and equipment addiional information (Details)
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40203 - Disclosure - Property and equipment: Purchase and installment payment agreements (Details)
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40401 - Disclosure - Long-term debt: Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes (Details)
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40402 - Disclosure - Long-term debt: Senior unsecured notes- $200.0 million 2021 Notes (Details)
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40403 - Disclosure - Long-term debt: Limitations under the Indentures (Details)
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40404 - Disclosure - Long-term debt: Senior secured notes-2018 Notes (Details)
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40503 - Disclosure - Income taxes: Net operating loss carry-forwards (Details)
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40504 - Disclosure - Income taxes: Reconciliation of unrecognized tax benefits (Details)
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40601 - Disclosure - Commitments and contingencies: (Details)
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40604 - Disclosure - Commitments and contingencies: Gain on capital lease termination (Details)
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40605 - Disclosure - Commitments and contingencies: Current and potential litigation (Details)
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40607 - Disclosure - Commitments and contingencies: Unconditional purchase obligations (Details)
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40608 - Disclosure - Commitments and contingencies: Defined contribution plan (Details)
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40701 - Disclosure - Stockholders' equity: (Details)
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40702 - Disclosure - Stockholders' equity: Common stock buyback program: (Details)
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40703 - Disclosure - Stockholders' equity: Dividends on common stock and return of capital program (Details)
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40801 - Disclosure - Stock option and award plan: Incentive award plan (Details)
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40802 - Disclosure - Stock option and award plan: Incentive award plan, tables (Details)
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40803 - Disclosure - Stock option and award plan: Non-vested awards, tables (Details)
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40804 - Disclosure - Stock option and award plan: Incentive award plan, additional information (Details)
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40901 - Disclosure - Related party transactions: (Details)
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41001 - Disclosure - Geographic information (Details)
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41101 - Disclosure - Quarterly financial information (unaudited): (Details)
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41201 - Disclosure - Subsequent Events: (Details)
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41301 - Disclosure - Schedule II VALUATION AND QUALIFYING ACCOUNTS (Details)
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