Disposal Group, Including Discontinued Operation, Ownership Interest Retained

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- Definition

Disposal Group, Including Discontinued Operation, Ownership Interest Retained, Percentage

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- Definition

Disposal Group, Including Discontinued Operations, Adjustments to AOCI

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- Definition

Amount after tax of an increase (decrease) to a gain (loss) previously reported in discontinued operations in a prior period.

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Amount of cash inflow (outflow) from (to) the discontinued operation after the disposal transaction.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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- Definition

Period of expected continuing involvement with a discontinued operation after the disposal date, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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No definition available.

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Amount of share in income (loss) of the equity method investee after the disposal of the discontinued operation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or the sale of investment in consolidated subsidiaries (generally greater than 50 percent).

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Business Dispositions and Discontinued Operations - Additional Information (Details) - USD ($) $ in Millions			3 Months Ended	12 Months Ended
	May 31, 2018	May 11, 2017	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Long-term Debt				$ 4,348.0	$ 4,265.0
Loss on discontinued operations				0.0	(202.0)	$ 3,257.0
Income (Loss) from Ongoing Equity Method Investment in Discontinued Operation after Disposal				66.0
Discontinued Operation, Amount of Continuing Cash Flows after Disposal				$ 67.0
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| P&C Runoff Subsidiaries
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business		$ 272.0
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds from sale of business	$ 1.4
Dividends paid	$ 300.0
Ownership interest retained, percentage	9.70%
Ownership interest retained	$ 164.0
Long-term Debt	142.0					142.0
Consideration received	1,500.0
Loss on discontinued operations						3,300.0
Discontinued Operation, Amount of Adjustment to Prior Period Gain (Loss) on Disposal, Net of Tax					202.0	(3,257.0)
Adjustments to AOCI	$ 758.0					$ 1,000.0	$ 758.0
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] \| Shadow DAC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Amount of Adjustment to Prior Period Gain (Loss) on Disposal, Net of Tax					10.0
Equity [Member] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Amount of Adjustment to Prior Period Gain (Loss) on Disposal, Net of Tax			$ (193.0)
Deferred Tax Asset [Domain] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Amount of Adjustment to Prior Period Gain (Loss) on Disposal, Net of Tax					(141.0)
Operating Income (Loss) [Member] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Amount of Adjustment to Prior Period Gain (Loss) on Disposal, Net of Tax					$ 104.0
Other Income [Member] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] \| Minimum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Period of Continuing Involvement after Disposal	5 years
Other Income [Member] \| Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] \| Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Period of Continuing Involvement after Disposal	24 months