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Impairments and Other Charges (Details)	3 Months Ended		9 Months Ended
Impairments and Other Charges (Details)	Sep. 30, 2021 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($) Segment	Sep. 30, 2020 USD ($)
Goodwill [Line Items]
Number of reporting units \| Segment			1
Proceeds from sale of assets			$ 39,163,000	$ 6,538,000
Impairment charge		$ 165,304,000
Impairment of intangible assets other than goodwill		148,909,000
Impairment of property and equipment		16,395,000
Goodwill impairment charge		387,970,000	219,052,000
Non-cash write-down		$ 8,000,000
Marine Transportation [Member]
Goodwill [Line Items]
Goodwill impairment charge	$ 219,052,000		$ 219,052,000
Marine Transportation [Member] \| Level 3 [Member]
Goodwill [Line Items]
Non-cash write-down	24,152,000
Marine Transportation [Member] \| HAWAII
Goodwill [Line Items]
Proceeds from sale of assets	17,200,000,000
Impairment charge	$ 97,508,000,000