Related Person Transactions - Purchase TA shares (Details) - TA - RMR LLC - USD ($) $ in Thousands	Sep. 30, 2020	Jul. 06, 2020	Oct. 10, 2018
Related Party Transaction [Line Items]
Share purchase from related party (in shares)	104,738	218,577	298,538
Purchase from related party	$ 2,259	$ 3,060	$ 8,382
Number of shares owned (in shares)	621,853
Ownership percentage	4.30%

Equity Method Investment, Number of Shares Owned

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- Definition

Related Party Transaction, Purchases From Related Party, Shares

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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- Details

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- Details

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