Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

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Amount of stock repurchase plan authorized.

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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)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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

+ References

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Stockholders' Equity - Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions		1 Months Ended
	Sep. 08, 2017	Jun. 30, 2017	May 31, 2017	Apr. 30, 2017
Share Repurchases
Authorized aggregate repurchases of common stock				$ 250.0
May 2017 Accelerated Share Repurchase Agreement
Share Repurchases
Payment for cost of accelerated share repurchase agreement entered			$ 250.0
Repurchased shares of common stock		1.7
Repurchased additional shares of common stock	0.3