Leases - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Weighted average remaining lease term	6 years 10 months 24 days
Option to terminate, term	1 year
Initial term of contract	12 months
Lease not yet commenced, amount	$ 33
Minimum
Lessee, Lease, Description [Line Items]
Weighted average remaining lease term	1 year
Renewal term	1 year
Term of contract	1 year
Maximum
Lessee, Lease, Description [Line Items]
Weighted average remaining lease term	50 years
Renewal term	50 years
Term of contract	15 years