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Income Taxes (Tables) | 12 Months Ended
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Dec. 31, 2016
Income Tax Disclosure [Abstract] |
Net deferred tax assets and liabilities | Net deferred tax assets and liabilities as of December 31, 2016 and 2015 are as follows:
(In thousands) |  | 2016 |  | 2015
Total deferred tax assets |  | $ | 636,449 |  |  | $ | 791,286 |
Total deferred tax liabilities |  | (28,794 | ) |  | (29,206 | )
Net deferred tax asset |  | $ | 607,655 |  |  | $ | 762,080 |
Components of the net deferred tax asset (liability) | The components of the net deferred tax asset as of December 31, 2016 and 2015 are as follows:
(In thousands) |  | 2016 |  | 2015
Unearned premium reserves |  | $ | 40,153 |  |  | $ | 33,262 |
Benefit plans |  | (12,350 | ) |  | (14,283 | )
Federal net operating loss |  | 520,812 |  |  | 680,975 |
Loss reserves |  | 10,883 |  |  | 15,536 |
Unrealized depreciation in investments |  | 11,211 |  |  | 8,904 |
Mortgage investments |  | 17,751 |  |  | 17,386 |
Deferred compensation |  | 12,517 |  |  | 12,927 |
Other, net |  | 6,678 |  |  | 7,373 |
Net deferred tax asset |  | 607,655 |  |  | 762,080 |
Summary of valuation allowance | The following table provides a rollforward of our deferred tax asset valuation allowance for the year ended December 31, 2015.
(In millions) |  | For the year ended December 31, 2015
Balance at December 31, 2014 |  | $ | 902.3 |
Reduction in tax provision in current year |  | (161.1 | )
Amounts recorded in other comprehensive income in the current year |  | 6.3 |
Change in valuation allowance for deferred tax assets in the current year |  | (154.8 | )
Reduction in tax provision for amounts to be realized in future years |  | (686.7 | )
Amounts recorded in other comprehensive income to be realized in future years |  | (60.8 | )
Change in valuation allowance for deferred tax assets realizable in future years |  | (747.5 | )
Balance at December 31, 2015 |  | $ | — |
Tax provision (benefit) | The effect of the change in valuation allowance on the provision for (benefit from) income taxes was as follows:
(In thousands) |  | 2016 |  | 2015 |  | 2014
Provision for income taxes before valuation allowance |  | $ | 172,197 |  |  | $ | 163,497 |  |  | $ | 91,607 |
Change in valuation allowance |  | — |  |  | (161,158 | ) |  | (88,833 | )
Reversal of the valuation allowance |  | — |  |  | (686,652 | ) |  | — |
Provision for (benefit from) income taxes |  | $ | 172,197 |  |  | $ | (684,313 | ) |  | $ | 2,774 |
Components of the provision for (benefit from) income taxes | The following summarizes the components of the provision for (benefit from) income taxes:
(In thousands) |  | 2016 |  | 2015 |  | 2014
Current Federal |  | $ | 9,470 |  |  | $ | 8,067 |  |  | $ | 2,391 |
Deferred Federal |  | 160,657 |  |  | (686,652 | ) |  | 1 |
Other |  | 2,070 |  |  | (5,728 | ) |  | 382 |
Provision for (benefit from) income taxes |  | $ | 172,197 |  |  | $ | (684,313 | ) |  | $ | 2,774 |
Reconciliation of federal statutory income tax rate | The reconciliation of the federal statutory income tax rate to the effective tax provision (benefit) rate is as follows:
| 2016 |  | 2015 |  | 2014
Federal statutory income tax rate | 35.0 | % |  | 35.0 | % |  | 35.0 | %
Valuation allowance | — | % |  | (173.8 | )% |  | (34.9 | )%
Tax exempt municipal bond interest | (1.9 | )% |  | (0.8 | )% |  | (0.4 | )%
Other, net | 0.4 | % |  | (0.7 | )% |  | 1.4 | %
Effective tax provision (benefit) rate | 33.5 | % |  | (140.3 | )% |  | 1.1 | %
Reconciliation of unrecognized tax benefits | A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
(In thousands) |  | 2016 |  | 2015 |  | 2014
Balance at beginning of year |  | $ | 107,120 |  |  | $ | 106,230 |  |  | $ | 105,366 |
Additions based on tax positions related to the current year |  | — |  |  | — |  |  | — |
Additions for tax positions of prior years |  | 1,125 |  |  | 890 |  |  | 864 |
Reductions for tax positions of prior years |  | — |  |  | — |  |  | — |
Settlements |  | — |  |  | — |  |  | — |
Balance at end of year |  | $ | 108,245 |  |  | $ | 107,120 |  |  | $ | 106,230 |

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- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 + Details
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