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The cash outflow to reacquire common stock during the period.

+ References

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-Publisher FASB
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-Topic 230
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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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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
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-Name Accounting Standards Codification
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Stockholders' Equity - Incentive and Other (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	6 Months Ended		135 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Mar. 29, 2007
Share Repurchase Program
Payments for Repurchase of Common Stock	$ 6,830	$ 3,816
Stock Repurchase Program 2007
Share Repurchase Program
Number of shares of outstanding common stock authorized to be acquired under a stock repurchase program	8.1		8.1	1.0
Share repurchase (in shares)			7.8
Average price (in dollars per share)	$ 41.19		$ 14.34
Payments for Repurchase of Common Stock	$ 6,800
Stock Repurchase Program 2007 \| Maximum
Share Repurchase Program
Share repurchase (in shares)	0.2