Leases - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Operating Leases
2019 (excluding the three months ended March 31, 2019)	$ 88,130
2020	91,969
2021	66,952
2022	47,742
2023	35,583
2024	23,792
Thereafter	32,605
Total lease payments	386,773
Less: imputed interest	(54,633)
Total operating lease liabilities	332,140
Less: current obligations	95,774	$ 0
Long-term lease obligations	$ 236,366	0
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019		118,827
2020		90,615
2021		64,501
2022		45,049
2023		32,771
Thereafter		50,998
Total minimum lease payments		$ 402,761

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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