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

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

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Amount of stock repurchase plan authorized.

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

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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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Stockholders' Equity - Additional Information (Details) - USD ($)								3 Months Ended		9 Months Ended
	Oct. 25, 2016	Aug. 26, 2016	Jul. 26, 2016	Jun. 07, 2016	Apr. 26, 2016	Mar. 17, 2016	Feb. 09, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Nov. 30, 2014
Subsequent Event [Line Items]
Cash dividends declared per common share (usd per share)			$ 0.07		$ 0.07		$ 0.07	$ 0.07	$ 0.06	$ 0.21	$ 0.18
Payments of common stock dividends		$ 4,200,000		$ 4,300,000		$ 4,300,000			$ 3,800,000	$ 12,800,000	$ 11,300,000
Value of shares repurchased										$ 33,800,000	10,600,000
April 2014 Repurchase Program
Subsequent Event [Line Items]
Authorized amount of common stock (shares)									$ 15,000,000		$ 15,000,000
Shares repurchased (shares)									394,430		724,792
Value of shares repurchased									$ 5,600,000		$ 10,600,000
November 2014 Repurchase Program
Subsequent Event [Line Items]
Authorized amount of common stock (shares)												$ 75,000,000
Shares repurchased (shares)								50,882		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