Income Taxes - Changes in Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 2,323	$ 2,200	$ 290
Additions based on tax positions related to the current year	0	0	0
Additions for tax positions of prior years	0	123	2,000
Reductions for tax positions of prior years	(2,000)	0	(90)
Settlements	(200)	0	0
Ending Balance	$ 123	$ 2,323	$ 2,200