00100 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS
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00200 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
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00300 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS
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40103 - Disclosure - Description of the business and recent developments: (Details 3)
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40301 - Disclosure - Long-term debt: (Details)
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40501 - Disclosure - Income taxes: (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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10101 - Disclosure - Description of the business and recent developments:
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10201 - Disclosure - Property and equipment:
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10301 - Disclosure - Long-term debt:
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10401 - Disclosure - Commitments and contingencies:
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10501 - Disclosure - Income taxes:
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10601 - Disclosure - Common stock buyback program:
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10701 - Disclosure - Dividends on common stock:
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10801 - Disclosure - Related party transactions:
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10901 - Disclosure - Segment information:
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20102 - Disclosure - Description of the business and recent developments: (Policies)
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30103 - Disclosure - Description of the business and recent developments: (Tables)
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30303 - Disclosure - Long-term debt: (Tables)
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30503 - Disclosure - Income taxes: (Tables)
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30703 - Disclosure - Dividends on common stock: (Tables)
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30903 - Disclosure - Segment information: (Tables)
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40101 - Disclosure - Description of the business and recent developments: (Details)
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40102 - Disclosure - Description of the business and recent developments: (Details 2)
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40104 - Disclosure - Description of the business and recent developments: (Details 4)
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40105 - Disclosure - Description of the business and recent developments: (Details 5)
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40201 - Disclosure - Property and equipment: (Details)
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40401 - Disclosure - Commitments and contingencies: (Details)
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40601 - Disclosure - Common stock buyback programs: (Details)
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40701 - Disclosure - Dividends on common stock: (Details)
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40801 - Disclosure - Related party transactions: (Details)
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40901 - Disclosure - Segment information: (Details)
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