Leases - Components of ROU Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Operating leases, ROU assets	$ 286,014
Finance leases, ROU assets	946
Total ROU assets	286,960
Operating leases, liabilities	309,228
Finance leases, liabilities	1,917
Lease liabilities	$ 311,145	$ 3,125