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Income Taxes (Narrative) (Detail) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Income Tax Contingency [Line Items] |  |  |  |  |  |
Effective income tax rate | 37.94% | [1] | 38.29% | [1] | 34.86% |
Reduction in its income tax provision resulting from the resolution of the tax matters |  |  |  |  | $ 10,900,000 |
Excess tax benefits related to stock-based awards, which increased the cash flow from financing activities | 6,200,000 |  | 7,100,000 |  | 3,000,000 |
Net operating loss carryforwards for federal and state tax | 14,900,000 |  | 9,400,000 |  | 20,700,000 |
Company's total liability for uncertain tax positions | 13,072,000 |  | 16,165,000 |  | 22,290,000 | 49,416,000
Uncertain tax positions recognized would favorably impact its effective tax rate | 12,700,000 |  |  |  |  |
Decrease in uncertain tax position | 3,100,000 |  | 6,100,000 |  |  |
Interest and penalties related to income tax liabilities | 300,000 |  | 400,000 |  | 1,700,000 |
Company's accrued liability for interest and penalties related to income tax liabilities | 9,000,000 |  | 8,700,000 |  |  |
Accounts payable and accrued expenses |  |  | 3,242,000 |  |  |
Increase in uncertain tax position | 1,100,000 |  |  |  |  |
Accounts Payable And Accrued Expenses [Member] |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Accounts payable and accrued expenses |  |  | 3,200,000 |  |  |
Other Liabilities [Member] |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Company's total liability for uncertain tax positions | 22,100,000 |  |  |  |  |
Other liabilities |  |  | 21,700,000 |  |  |
Other Liabilities [Member] | Accounts Payable And Accrued Expenses [Member] |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Company's total liability for uncertain tax positions |  |  | $ 24,900,000 |  |  |
[1] | The comparison of net income is affected by the change in the effective tax rate. The effective tax rate was 37.94% for the year ended December 31, 2012 as compared to 38.29% for the year ended December 31, 2011.

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