Leases - Narrative (Details)	6 Months Ended
	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Termination period of leases	1 year
Weighted-average discount rate used for operating leases (as a percent)	4.39%
Weighted-average discount rate used for finance leases (as a percent)	1.78%
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	14 years
Renewal term of operating leases	7 years
Renewal term of finance leases	7 years