General - Components of Lease Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Components of leases expenses:
Operating lease cost	$ 4,657	$ 9,382
Amortization of right-of-use asset	1,018	1,958
Interest on lease liabilities	418	634
Total finance lease cost	1,436	2,592
Short-term lease cost	346	664
Variable lease cost	690	1,564
Total lease cost	7,129	14,202
Sublease income	(102)	(200)
Net lease cost	$ 7,027	$ 14,002

Total finance lease cost, including but not limited to, amortization of right-of-use assets and interest expense.

No definition available.

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- Definition

Total operating and finance least cost excluding sublease income.

+ References

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- References

No definition available.

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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
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-SubTopic 20
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-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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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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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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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

+ Details

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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

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