Fair Value Measurement - Cash and Cash Equivalents Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Cash Equivalents, at Carrying Value [Abstract]
Cash equivalents	$ 28,091	$ 10,057	$ 46,094
Cash	141,410	179,269	152,204
Total cash and cash equivalents	$ 169,501	$ 189,326	$ 198,298	$ 252,836