Segment Information - Revenue Classified by Major Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015		Jun. 30, 2016	Jun. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 212,074	$ 227,959	[1]	$ 427,030	$ 465,134	[1]
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	202,821	218,748		406,290	443,393
United Kingdom Israel [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	8,440	8,332		19,032	19,304
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 813	$ 879		$ 1,708	$ 2,437

[1] Amounts have been recast to reflect discontinued operations. See Note 3 for details.