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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Jun. 30, 2016
Income Tax Contingency [Line Items] |  |  |  |  |
U.S. statutory rate (as a percent) |  |  | 35.00% | 35.00% |
Income tax expense (benefit) | $ (4.0) | $ (17.1) | $ (5.3) | $ (22.7) |
Effective income tax rate reconciliation, percent | (47.60%) | (123.90%) | (203.90%) | (31.20%) |
Tax Year 2012 |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Deferred tax assets, gross |  |  |  |  | $ 0.6
Operating loss carryforwards, valuation allowance |  |  |  |  | $ 0.6
Continuing Operations |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax expense (benefit) |  |  |  | $ (14.0) |
Continuing Operations | BAM |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax expense (benefit) | $ (2.1) | $ (3.3) | $ (6.9) | $ (8.2) |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319 + Details
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