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Earnings Per Share (Narrative) (Details) - USD ($) |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 30, 2013 | May. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Issuance of stock at the separation and distribution, shares | 46,743,316 |  |  |
Stock repurchase program, shares acquired |  |  | 5,088,434 | 1,056,689
May 2014 Share Repurchase Program [Member] |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Stock repurchase program, approved amount |  | $ 50,000,000 |  |
Stock repurchase program, shares acquired |  | 1,040,636 |  |
Stock repurchase program, average price per share (in dollars per share) |  | $ 48.07 |  |
Two Hundred Fifty Million Dollar Share Repurchase Program [Member] |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Stock repurchase program, approved amount |  |  | $ 250,000,000 |
Stock repurchase program, shares acquired |  |  | 4,196,349 |
Stock repurchase program, average price per share (in dollars per share) |  |  | $ 59.58 |

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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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