Leases - Components of Lease Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Finance lease cost:
Amortization of lease assets	$ 1,234	$ 1,393
Interest on lease liabilities	107	64
Operating lease cost	116,672	121,767
Short-term and variable lease cost	656,649	837,244
Total lease cost	$ 774,662	$ 960,468

Finance Leases, Cost [Abstract]

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- Definition

Amount of interest expense on finance lease liability.

+ References

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-Publisher FASB
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-SubTopic 20
-Section 50
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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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+ Details

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
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-Name Accounting Standards Codification
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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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