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Discontinued Operations - EPS (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Equity in earnings of unconsolidated affiliates, net of tax | $ 0.0 | $ 3.9 | $ 0.0 | $ 18.0
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 11,943 |  | 8,208 |
Income (Loss) Allocated to Participating Unvested Restricted Common Shares | $ 0.4 | 0.0 | $ 0.3 | 0.0
Net Income (Loss) Available to Common Stockholders, Basic | $ 91.7 | $ (58.9) | $ 445.8 | $ 29.7
Total average common shares outstanding during the period | 4,867,400 | 5,890,100 | 5,166,600 | 5,951,100
Average unvested restricted common shares | (68,100) | 0 | (62,900) | 0
Basic earnings per share denominator | 4,799,300 | 5,890,100 | 5,103,700 | 5,951,100
Average outstanding dilutive options to acquire common shares | 4,879,400 | 5,890,100 | 5,174,800 | 5,951,100
Diluted earnings (loss) per share denominator | 4,811,300 | 5,890,100 | 5,111,900 | 5,951,100
Earnings Per Share, Diluted | $ 18.80 | $ (10.01) | $ 86.13 | $ 4.97
Discontinued Operations [Member] |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Net loss from discontinued operations, net of tax | $ 61.9 | $ 6.5 | $ 421.6 | $ 77.3
Income (Loss) Allocated to Participating Unvested Restricted Common Shares | (0.9) | (0.1) | 5.1 | (0.9)
Net Income (Loss) Available to Common Stockholders, Basic | $ 61.0 | $ 6.4 | $ 416.5 | $ 76.4
Total average common shares outstanding during the period | 4,879,400 | 5,890,100 | 5,174,800 | 5,951,100
Average unvested restricted common shares | (68,100) | (70,900) | (62,900) | (67,100)
Basic earnings per share denominator | 4,799,300 | 5,819,200 | 5,103,700 | 5,884,000
Diluted earnings (loss) per share denominator | 4,811,300 | 5,819,200 | 5,111,900 | 5,884,000
Earnings Per Share, Basic | $ 12.72 | $ 1.09 | $ 81.60 | $ 12.98
Earnings Per Share, Diluted | $ 12.69 | $ 1.09 | $ 81.47 | $ 12.98
Common Stock [Member] | Symetra |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Equity in earnings of unconsolidated affiliates, net of tax |  | $ 4.2 |  | $ 17.5
Amortization of common share basis difference | Common Stock [Member] | Symetra |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Equity in earnings of unconsolidated affiliates, net of tax |  | $ 0.7 |  | $ 2.1
Employee Stock Option [Member] |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 120,000 |  | 120,000 |

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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.21) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1252-109256 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 + Details
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- Definition This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.12) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 + Details
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- Definition Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e2646-109256 + Details
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