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Share-Based Compensation - Fully-vested Common Stock Issued to Non-employee Directors (Details) - Common Stock - Non-employee Directors shares in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($) director shares	Sep. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of non-employee directors to whom fully vested common stock is granted | director	6
Awards issued (in shares) | shares	51	68
Grant date fair value of awards issued | $	$ 525	$ 326

X

- Definition

Represents the number of non-employee directors to whom fully vested common stock is granted.

+ References

No definition available.

+ Details

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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