Restructuring (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended	21 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charges incurred			$ 7,000		$ 19,300	$ 62,600
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2019			10,981
Costs incurred	$ 790	$ 266	7,179	$ 15,174
Cash disbursements			(15,539)
Balance as of June 30, 2019	2,621		2,621		2,621	2,621
Employee Severance and Related Benefits
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2019			10,508
Costs incurred			7,119
Cash disbursements			(15,227)
Balance as of June 30, 2019	2,400		2,400		2,400	2,400
Software Charges
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2019			198
Costs incurred			0
Cash disbursements			(99)
Balance as of June 30, 2019	99		99		99	99
Excess Facilities, Contract Terminations and Other
Restructuring Reserve [Roll Forward]
Balance as of January 1, 2019			275
Costs incurred			60
Cash disbursements			(213)
Balance as of June 30, 2019	$ 122		$ 122		$ 122	$ 122