Income Taxes - Unrecognized tax benefits (Details) - USD ($) |
12 Months Ended | |
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Dec. 31, 2015 |
Dec. 31, 2014 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | ||
| Balance, beginning of year | $ 3,700,000 | $ 9,200,000 |
| Additions for prior year tax positions | 200,000 | 1,700,000 |
| Settlements paid to tax authorities | 0 | 0 |
| Reductions of prior year tax positions | (1,700,000) | (7,200,000) |
| Balance, end of year | $ 2,200,000 | $ 3,700,000 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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