Restructuring - Activity (Details) - USD ($) $ in Thousands	3 Months Ended				11 Months Ended	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Additions/Reductions charged to expense	$ 1,200	$ 300	$ 600	$ 13,700		$ 15,806	$ 0	$ 0
Restructuring Plan
Restructuring Reserve [Roll Forward]
Additions/Reductions charged to expense					$ 15,456
Cash payments					(13,109)
Balance at September 30, 2020	2,347				2,347	2,347
Severance and other benefits | Restructuring Plan
Restructuring Reserve [Roll Forward]
Additions/Reductions charged to expense					12,107
Cash payments					(10,626)
Balance at September 30, 2020	1,481				1,481	1,481
Other Restructuring | Restructuring Plan
Restructuring Reserve [Roll Forward]
Additions/Reductions charged to expense					3,349
Cash payments					(2,483)
Balance at September 30, 2020	$ 866				$ 866	$ 866