Description of Business and Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Recent Accounting Pronouncements
Revenue	$ 122,517	$ 140,891	$ 234,035	$ 269,173
Operating expenses:
Cost of services and products, exclusive of depreciation and amortization	24,752	50,364	48,835	94,878
Presented without adoption of ASC 606
Recent Accounting Pronouncements
Revenue		$ 140,891		$ 269,173
ASU 2014-09 | Adjustment
Recent Accounting Pronouncements
Revenue	27,470		51,374
Operating expenses:
Cost of services and products, exclusive of depreciation and amortization	27,470		51,374
ASU 2014-09 | Presented without adoption of ASC 606
Recent Accounting Pronouncements
Revenue	149,987		285,409
Operating expenses:
Cost of services and products, exclusive of depreciation and amortization	$ 52,222		$ 100,209