Commitments And Contingencies And Other Matters - Lease Commitments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	$ 122,501
2020	102,140
2021	94,401
2022	95,435
2023	55,799
Thereafter	10,448
Total lease commitments	480,724
Vessels
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	116,620
2020	96,800
2021	89,216
2022	90,371
2023	51,266
Thereafter	0
Total lease commitments	444,273
Facilities and Other
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	5,881
2020	5,340
2021	5,185
2022	5,064
2023	4,533
Thereafter	10,448
Total lease commitments	$ 36,451

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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