Income Taxes Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Pre-tax loss at U.S. statutory rate	35.00%	35.00%	35.00%
Dividend received deduction	(25.90%)	(0.00%)	(0.00%)
Bargain purchase gain	(34.80%)	0.00%	0.00%
Basis adjustment on investments	65.20%	0.00%	0.00%
Nondeductible expenses	14.20%	0.00%	0.00%
Deferred asset recognition	0.00%	0.00%	(323.80%)
Unrecognized gains on foreign subsidiaries	0.00%	38.70%	0.00%
Change in valuation allowance	0.00%	(6.70%)	0.00%
Impact of tax law change	669.80%	0.00%	(27.90%)
State and foreign tax	25.30%	1.30%	(39.60%)
Reversal of income attributable to redeemable non-controlling interests	(119.60%)	1.30%	(46.50%)
Other, net	3.70%	(9.00%)	(11.00%)
Total	632.90%	60.60%	(413.80%)

Effective Income Tax Rate Reconciliation, Bargain Purchase Gain, Percent

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Effective Income Tax Rate Reconciliation, Basis Adjustment on Investment, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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