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Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Deferred tax assets related to: |  |
U.S. federal and state net operating and capital loss carryforwards | $ 102.8 | $ 79.6
Non-U.S. net operating loss carryforwards | 47.1 | 50.5
Incentive compensation | 14.6 | 17.5
Accrued interest | 10.8 | 7.9
Deferred acquisition costs | 6.4 | 5.5
Tax credit carryforwards | 4.9 | 5.5
Other items | 0.7 | 1.3
Total gross deferred tax assets | 187.3 | 167.8
Less: valuation allowances | 92.3 | 97.4
Total net deferred tax assets | 95.0 | 70.4
Deferred tax liabilities related to: |  |
Member’s surplus contributions | 60.4 | 52.9
Purchase accounting | 48.5 | 5.1
Investment basis difference | 33.7 | 11.8
Net unrealized investment gains (losses) | 10.7 | 0.3
Deferred underwriting | 4.1 | 0.0
Other items | 2.7 | 2.8
Total deferred tax liabilities | 160.1 | 72.9
Net deferred tax asset (liability) | $ (65.1) | $ (2.5)

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