Shareholders' Equity Shareholders' Equity Note (Detail textual) (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Feb. 07, 2019
Stockholders' Equity Note [Abstract]
Stock Repurchased During Period, Shares			2.5
Stock Repurchase Program, Number of Shares Authorized to be Repurchased					15.0
Repurchase of common stock	$ 75,000	$ 0	$ 124,996	$ 99,957
Payments for Repurchase of Common Stock			$ (124,996)	$ (99,957)

The cash outflow to reacquire common stock during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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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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- 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.

+ References

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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