Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes
Federal statutory income tax rate (as a percent)	35.00%
Reconciliation of income taxes:
Income tax expense computed at federal statutory income tax rate	$ 31,229	$ 11,252	$ 14,723
Foreign taxes, net of credits	(1,804)	418	2,835
Net adjustments for uncertain tax positions	706	4,731	525
State and local taxes	(525)	(1,108)	(1,659)
Equity appreciation rights	372	693
Transaction costs	3,078	414
Indemnified taxes	1,594	(1,106)
Fair value adjustment for common stock warrants	3,029	10,853	268
Valuation allowance	955	7,872	2,476
Deferred charge	1,009	807	(1,491)
Tax credits	(704)	(7,003)	(2,176)
Miscellaneous other, net	768	171	1,199
Income tax expense as reported	$ 39,707	$ 27,994	$ 16,700
Effective income tax rate (as a percent)	44.50%	87.10%	39.70%