Other	9 Months Ended
Other	Sep. 30, 2018
Debt and Other Disclosures [Abstract]
Debt Disclosure	Debt In July 2018, our $200.0 million 7.00% senior unsecured notes matured. In May 2018, we issued $300.0 million of 6.25% junior subordinated notes due 2058. The notes are redeemable at or above par on or after June 15, 2023 and rank equally in the right of payment with our other junior subordinated debt securities. During the nine months ended September 30, 2018, we made principal payments of $45.0 million on our senior secured non-recourse notes issued by Northwind Holdings, LLC. At September 30, 2018, letters of credit totaling $2.1 million had been issued from the credit facility, but there were no borrowed amounts outstanding. In June 2017, we purchased and retired the remaining $3.4 million of principal on our senior secured floating rate notes acquired through our purchase of Starmount. In conjunction with this retirement, we also terminated the interest rate swap associated with the hedge of these notes and recorded a $0.1 million loss in our consolidated statements of operations as a component of net realized investment gains and losses. See Note 5 for further discussion.
Income Tax Disclosure	Income Tax On December 22, 2017, the U.S. Federal government enacted the TCJA, which reduces the federal corporate tax rate from 35 percent to 21 percent effective January 1, 2018. Securities and Exchange Commission Staff Accounting Bulletin (SAB) 118 has provided guidance for companies that have not completed their accounting for the income tax effects of the TCJA, allowing for a measurement period of up to one year after the enactment date to finalize the recording of the related tax impacts. During the fourth quarter of 2017, our income tax expense included a provisional benefit of $31.5 million, consisting of a $97.9 million benefit related to the revaluation of our net deferred tax liabilities associated with our U.S. operations to the newly enacted U.S. corporate tax rate and a tax expense of $66.4 million resulting from the tax on undistributed and previously untaxed foreign earnings and profits (Repatriation Tax). As of September 30, 2018, we have not completed our accounting for the tax effects of the enactment of the TCJA; however, we increased our provisional Repatriation Tax estimate by $11.5 million to $77.9 million. We will continue to refine our calculations as additional analysis is completed and record the final amounts during the one year measurement period after the enactment date as allowed by SAB 118. Tax rate estimates recorded at December 31, 2017 and September 30, 2018 may be impacted by changes in accounting and tax interpretations of the TCJA legislation. During the third quarter of 2018, we recorded a $266.5 million gross unrecognized tax benefit liability for a tax reserving position we have taken on our 2017 tax return which, if recognized, would decrease our tax expense by $112.9 million. We recognize interest expense and penalties, if applicable, related to unrecognized tax benefits in tax expense, net of federal income tax. We have not recorded penalties with respect to the unrecognized tax benefit recorded in the third quarter of 2018 as the technical merits of the position have authority to prevent any assessment of penalty. We have not recorded interest with respect to the unrecognized tax benefit, as we currently have sufficient funds on account with the IRS to prevent the accrual of interest. We believe it is reasonably possible this item could reverse in the next 12 months.