Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of year	$ 2,155	$ 4,009	$ 3,428
Additions as a result of a tax position taken during the current period	830	675	600
Reductions as a result of tax positions taken during a prior period	0	0	(19)
Reductions relating to settlement with taxing authorities	(1,500)	(2,529)	0
Unrecognized tax benefits at end of year	$ 1,485	$ 2,155	$ 4,009