Related party expenses.

No definition available.

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- Definition

Related party income.

+ References

No definition available.

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Balance Type:	debit
Period Type:	duration

- Definition

Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

+ References

No definition available.

+ Details

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

- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

Reference 2: 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=121568110&loc=SL77918982-209971

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

- Details

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Related Party Transactions - Schedule of Components of Related Party Revenues and Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party income
Related party income	$ 1,529	$ 2,412	$ 5,303	$ 7,183	$ 9,263	$ 8,810	$ 0
Sublease revenue	753	996	2,366	2,947	3,942	3,366	0
Related party expenses
Total related party expenses					286	612	0
TSA Compensation Related
Related Party income
Related party income	586	974	1,735	3,110	3,837	4,280	0
Related party expenses
Total related party expenses					176	588	0
TSA Non Compensation Related
Related Party income
Related party income	160	442	497	1,126	1,484	1,164	0
Related party expenses
Total related party expenses					110	24	0
TSA
Related Party income
Related party income	$ 1,499	$ 2,412	$ 4,598	$ 7,183	$ 9,263	$ 8,810	$ 0