Leases (Narrative) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Capital leased assets
Weighted average remaining lease term	15 years 7 months 6 days
Discount rate	4.20%
Weighted average remaining finance lease term	3 years 6 months
Finance discount rate	3.80%
Future minimum sublease payments	$ 451,000
Net book value	$ 477,327,000	$ 484,482,000
Minimum [Member]
Capital leased assets
Operating lease fixed term	1 month
Finance lease term	1 month
Maximum [Member]
Capital leased assets
Operating lease fixed term	20 years
Finance lease term	6 years
Computer Equipment [Member]
Capital leased assets
Net book value	$ 6,951,000	7,482,000
Yard And Others [Member]
Capital leased assets
Net book value	16,866,000	15,776,000
Finance leases [Member]
Capital leased assets
Net book value	23,817,000	23,258,000
Net book value	$ 23,817,000	$ 23,258,000

Lessee, Finance Sublease, Future Minimum Payments

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No definition available.

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The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Discount rate used by lessee to determine present value of finance lease payments.

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Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Discount rate used by lessee to determine present value of operating lease payments.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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