Leases - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) ft²	Apr. 30, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)	Oct. 31, 2018 USD ($) ft²
Lessee, Lease, Description [Line Items]
Operating and finance lease, maximum term of extension option	5 years
Operating and finance lease, term of termination option	1 year
Area of space leased (in square feet) | ft²	1,000,000,000,000
Restructuring reserve			$ 85,800
Total base rent obligation	$ 556,690
Nashville
Lessee, Lease, Description [Line Items]
Area of space leased (in square feet) | ft²				218,976
Operating lease, lease not yet commenced, term of contract				15 years
Total base rent obligation				$ 134,000
New York City
Lessee, Lease, Description [Line Items]
Area of space leased (in square feet) | ft²		190,000
Operating lease, lease not yet commenced, term of contract		20 years
Total base rent obligation		$ 448,000
Minimum
Lessee, Lease, Description [Line Items]
Operating and finance lease, remaining contract term	1 year
Minimum | New York City
Lessee, Lease, Description [Line Items]
Area of space leased (in square feet) | ft²	190,000
Total base rent obligation	$ 448,000
Maximum
Lessee, Lease, Description [Line Items]
Operating and finance lease, remaining contract term	15 years
Maximum | New York City
Lessee, Lease, Description [Line Items]
Area of space leased (in square feet) | ft²	166,000
Total base rent obligation	$ 393,000