Leases - Estimated Minimum Future Lease Payments (Details) - USD ($) $ in Thousands	Mar. 24, 2020	Dec. 31, 2019
Finance Lease Liabilities
Present value of lease obligations	$ 293	$ 574
Operating Lease Liabilities
Present value of lease obligations	282,888	$ 275,209
Company as Lessee
Finance Lease Liabilities
2020	134
2021	138
2022	19
2023	17
2024	16
Thereafter	4
Total lease payments	328
Amounts representing interest	(35)
Present value of lease obligations	293
Operating Lease Liabilities
2020	29,012
2021	39,100
2022	40,845
2023	35,751
2024	29,975
Thereafter	252,220
Total lease payments	426,903
Amounts representing interest	(144,015)
Present value of lease obligations	282,888
Operating Subleases
2020	(4,761)
2021	(6,247)
2022	(6,802)
2023	(6,120)
2024	(5,463)
Thereafter	(60,760)
Total lease payments	(90,153)
Net Lease Commitments
2020	24,385
2021	32,991
2022	34,062
2023	29,648
2024	24,528
Thereafter	191,464
Total lease payments	337,078
Amounts representing interest	(144,050)
Present value of lease obligations	$ 193,028

Lessee, Operating and Finance Lease, Liability, Net Of Sublease Income, Undiscounted Excess Amount

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Present value of lessee's discounted obligation for lease payments from finance 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=77888426&loc=SL77918701-209980

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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-Section 45
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981

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-SubTopic 30
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-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981

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

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