Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Effective Income Tax Rate, Percent	(0.70%)	28.60%
Valuation Allowance [Abstract]
Valuation Allowance, Amount	$ 0		$ 0
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	3,900		4,800
Unrecognized Tax Benefits, Period Increase (Decrease)	(1,200)	$ (1,700)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	1,500		$ 2,300
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	(800)	$ (800)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance beginning of period	5,839
Additions based on tax positions related to current year	41
Additions for tax positions of prior years	0
Reductions for tax positions of prior years	0
Reductions due to lapse of applicable statute of limitations	(1,249)
Settlements	0
Balance end of period	4,631
Maximum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	(2,000)
Minimum [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	$ (1,000)