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

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ 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 (i)
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-SubTopic 10
-Section 50
-Paragraph 2
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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

Percentage of vesting of share-based compensation awards.

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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Number of new stock issued during the period.

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-Topic 210
-SubTopic 10
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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) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Aug. 31, 2010	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
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		1,363,211
Repurchase of common stock shares	1,500,000	0	0
Dividend Reinvestment and Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period shares		1,503	546
Maximum common stock issuable under plan		1,550,000
Shares available for issuance under plan		1,545,460
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum Vesting Period		4 years
Rate of restricted stock units vest under plan		25.00%
Compensation expense related to non-vested awards not yet recognized		$ 4,443
Weighted-average vesting period for compensation expenses not yet recognized		2 years 8 months 12 days