Accumulated Other Comprehensive Income Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) Roll Forward [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	$ 0
Other Comprehensive Income Loss Reclassification Adjustments Total Net of Tax	0
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0		$ 0
Unrealized gain on available-for-sale investments, net of tax (benefit)	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	3,582
Other Comprehensive Income Loss Arising During Period Total Net of Tax	3,582
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	0
Foreign currency translation adjustment	3,582	$ 3,415
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	(54,649)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	(51,067)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0	(2,361)
Other Comprehensive Income (Loss), Net of Tax	3,582	$ 1,054
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ (51,067)		$ (54,649)