Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 230
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-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Stockholders' Equity - Additional Information (Details) - USD ($)					3 Months Ended				9 Months Ended
	Oct. 24, 2017	Jul. 25, 2017	Apr. 21, 2017	Feb. 17, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Nov. 30, 2014
Subsequent Event [Line Items]
Cash dividends declared per common share (usd per share)		$ 0.07	$ 0.07	$ 0.07	$ 0.07			$ 0.07	$ 0.21	$ 0.21
Payments of common stock dividends					$ 4,200,000	$ 4,200,000	$ 4,200,000	$ 4,200,000	$ 12,600,000	$ 12,800,000
Value of shares repurchased										$ 33,800,000
November 2014 Repurchase Program
Subsequent Event [Line Items]
Authorized amount of common stock (shares)											$ 75,000,000
Shares repurchased (shares)					0			50,882	0	2,631,607
Value of shares repurchased								$ 700,000		$ 33,800,000
Subsequent Event
Subsequent Event [Line Items]
Cash dividends declared per common share (usd per share)	$ 0.07