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Share-Based Payments (Details 9) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Shares issued under ESPP | 6,200,000 |  |
2015 ESPP |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Shares issued under ESPP | 78,000 |  |
Cash received under ESPP | $ 19.3 |  |
1995 ESPP |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |
Shares issued under ESPP | 98,000 | 180,000 | 245,000
Cash received under ESPP | $ 30.0 | $ 46.4 | $ 38.7

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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. + References Reference 1: 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 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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