Aggregate number of common shares reserved for future issuance.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ 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

Percentage of vesting of award 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
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Number of new stock issued during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity - Additional Information (Detail) - shares	1 Months Ended	3 Months Ended
Equity - Additional Information (Detail) - shares	Aug. 31, 2010	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum common stock issuable under plan		22,500,000		22,500,000
Stock buyback program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance under plan		596,368
Repurchase of common stock shares	1,500,000
Dividend Reinvestment and Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period shares		2,817	3,298
Maximum common stock issuable under plan		1,550,000
Shares available for issuance under plan		1,526,712
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Rate of restricted stock units vest under plan		25.00%