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Common Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Feb. 28, 2017 | Nov. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2016
Stock Repurchase Program [Line Items] |  |  |  |
Cash paid for repurchase of common stock |  |  | $ 250,000,000 |
Maximum capital allocated for repurchases of shares |  |  |  | $ 750,000,000
Accelerated Share Repurchase Agreement (ASR) [Member] |  |  |  |
Stock Repurchase Program [Line Items] |  |  |  |
Common stock repurchases |  | $ 225,000,000 |  |
Shares of common stock received under ASR | 0.4 | 2.8 |  |
Cash paid for repurchase of common stock |  | $ 225,000,000 |  |
Accelerated share repurchase, price per share |  | $ 63.41 |  |
Accelerated Share Repurchase Agreement (ASR) [Member] | Weighted Average [Member] |  |  |  |
Stock Repurchase Program [Line Items] |  |  |  |
Final weighted average per share purchase price during the repurchase period | $ 69.43 |  |  |

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- Definition Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time. + References 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 + Details
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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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