Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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Amount of expense for amortization of capitalized computer software costs.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The amount of accumulated amortization attributable to finance lease right of use assets at balance sheet date.

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Amount expended to purchase right of use asset under finance lease.

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Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Depreciation	$ 84,600	$ 85,900	$ 86,000
Losses on sale of equipment	3,853	7,123	2,029
Finance leases, cost, post-adoption	29,500
Capitalized leases, cost, pre-adoption		39,500
Finance leases, accumulated amortization, post-adoption	15,900
Capitalized leases, accumulated amortization, pre-adoption		18,100
Capitalized computer software, amortization	4,100	3,100	$ 3,800
Capitalized computer software, accumulated amortization	$ 64,200	$ 60,200
Minimum [Member]
Property, Plant and Equipment [Line Items]
Finance lease Term	1 year
Maximum [Member]
Property, Plant and Equipment [Line Items]
Finance lease Term	15 years
Revenue and service equipment \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Finance lease Term	24 months
Revenue and service equipment \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Finance lease Term	100 months