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Income Taxes (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Income Taxes [Abstract] |  |  |
PortionOfTaxBenefitRecordedPositionsMoreLikelyThanNotToBeSustained | 50.00% |  |
Income Tax Uncertainties [Abstract] |  |  |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | $ 5,700 | $ 7,300 |
Unrecognized Tax Benefits, Period Increase (Decrease) | (2,800) | (1,100) |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 3,200 | 4,700 |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | (1,500) | (1,000) | $ (1,000)
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound | (1,800) |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound | (2,800) |  |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] |  |  |
Balance beginning of period | 11,569 | 12,632 |
Additions based on tax positions related to current year | 592 | 954 |
Additions for tax positions of prior years | 0 | 0 |
Reductions for tax positions of prior years | (108) | (90) |
Reductions due to lapse of applicable statute of limitations | (3,302) | (1,927) |
Settlements | 0 | 0 |
Balance end of period | 8,751 | 11,569 | 12,632
Valuation Allowance [Abstract] |  |  |
Valuation Allowance, Amount | 0 | 0 |
Income Tax Reconciliation, Tax Contingencies | $ (1,473) | $ (1,006) | $ (993)

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in income tax contingencies. Including, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319 + Details
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + Details
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