Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Leases [Abstract]
Operating lease cost	$ 26,506	$ 53,648
Financing lease cost:
Amortization of right-of-use assets	291	577
Interest on lease liabilities	15	32
Total finance lease cost	306	609
Variable lease cost	9,876	19,749
Sublease income	(13,988)	(28,451)
Net lease cost	$ 22,700	$ 45,555

Finance Lease, Cost

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest expense on finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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-Name Accounting Standards Codification
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+ Details

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Period Type:	duration

- Definition

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

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- 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
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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+ Details

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- References

No definition available.

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- References

No definition available.

+ 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
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

+ Details

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Balance Type:	credit
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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

+ Details

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