LEASES - Lease expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
LEASES
Amortization of right-of-use assets	$ 597	$ 704	$ 14,608
Interest on lease liabilities	147	377	2,085
Operating lease cost	2,404	3,873	9,169
Short-term lease cost	200	84	464
Variable lease cost	1,306	1,375	1,360
Total lease cost	4,654	6,413	27,686
Rental expense	$ 3,300	$ 5,200	$ 11,000

Amount of interest expense on finance lease liability.

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=123408670&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Balance Type:	debit
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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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-Publisher FASB
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

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-Publisher FASB
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-SubTopic 20
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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 variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

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