Restructuring and Related Impairment Charges - 2020 restructuring Plan (Details) - 2020 Restructuring Plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring and related impairment charges	$ 16,763	$ 70,232	$ 26,897	$ 410,258
Restructuring and related impairment charges recorded to date	499,600		499,600
Cash Restructuring Charges
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					$ 199,000
Facilities and Lease Terminations
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					14,000
Employee Related Costs
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					28,000
Contract Termination And Other Restructuring
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					157,000
Non-Cash Charges
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					376,000
Long-Lived Asset Impairment
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					291,000
Intangible and Other Asset Impairment
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs					85,000
Minimum
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs	525,000		525,000		550,000
Maximum
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs	$ 575,000		$ 575,000		$ 600,000