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Income Taxes (Deferred Tax Inventory) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Deferred income tax assets related to: |  |
U.S. federal and state net operating and capital loss carryforwards | $ 73.0 | $ 104.3
Non-U.S. net operating loss carryforwards | 33.9 | 34.0
Compensation | 20.4 | 26.5
Investment basis difference | 4.9 | 5.6
Other items | 4.9 | 8.5
Total gross deferred income tax assets | 137.1 | 178.9
Less: valuation allowances | 109.6 | 146.2
Total net deferred income tax assets | 27.5 | 32.7
Deferred income tax liabilities related to: |  |
Other items | 2.1 | 2.7
Total deferred income tax liabilities | 26.2 | 32.7
Net deferred tax asset | 1.3 | 0.0
Members Surplus Contributions |  |
Deferred income tax liabilities related to: |  |
Deferred tax liabilities, members surplus contributions | $ 24.1 | $ 30.0

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