Leases - Lease Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Lease Payments
2021	$ 138,403
2022	133,854
2023	130,627
2024	120,092
2025	115,279
Thereafter	549,496
Total future minimum operating lease payments	1,187,751
Imputed interest	(323,590)
Total operating lease liabilities per the Consolidated Balance Sheet	864,161	$ 909,049
Sublease Cash Receipts
2021	44,446
2022	47,965
2023	48,909
2024	40,629
2025	40,989
Thereafter	102,510
Total future estimated sublease cash receipts	$ 325,448
UNITED STATES
Lessee, Lease, Description [Line Items]
Percentage of lease payments	80.00%

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of lease payments to be received by lessor for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919396-209981

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Amount of lease payment to be received by lessor for operating lease in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lease payment to be received by lessor for operating lease in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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