Quarterly report pursuant to Section 13 or 15(d)

Leases Narrative (Details)

v3.21.2
Leases Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Restructuring $ 0 $ 23 $ (1) $ 25  
Restructuring Plan 2020 [Member]          
Restructuring         $ 37
Facility Closing [Member]          
Restructuring     $ 0    
COVID-19 [Member] | Restructuring Plan 2020 [Member]          
Restructuring         $ 36
COVID-19 [Member] | Travel and Membership | Facility Closing [Member] | Restructuring Plan 2020 [Member]          
Restructuring   22      
COVID-19 [Member] | Asset Impairments [Member] | Travel and Membership          
Operating Lease, Impairment Loss   $ 24      
Minimum [Member]          
Lessee, Operating Lease, Remaining Lease Term 1 year   1 year    
Maximum [Member]          
Lessee, Operating Lease, Remaining Lease Term 20 years   20 years    
Lessee, Operating Lease, Renewal Term 10 years   10 years    
Lessee, Operating Lease, Termination Period     1 year