Reconciliation of Total Amounts of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Beginning balance of unrecognized tax benefits	$ 5,490	$ 6,274	$ 7,074
Additions based on tax positions related to the current year	561	752	1,180
Additions for tax positions of prior years	88	78	2,601
Reductions for tax positions of prior years	(45)	(626)	(2,404)
Reductions to tax positions resulting from a lapse of the applicable statute of limitations	(842)	(226)	(2,177)
Settlements with taxation authorities	(290)	(762)
Ending balance of unrecognized tax benefits	$ 4,962	$ 5,490	$ 6,274