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Income Taxes - Carryforwards (Details) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
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Components of deferred tax assets and liabilities |  |
Deferred Tax assets related to net unrealized losses on held-to-maturity securities transferred from available-for-sale securities | $ 2.4 | $ 2.8
Alternative minimum tax credit |  |
Net operating loss carryforward |  |
Alternative minimum tax credit that can be carried forward | 1.7 |
Federal |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 68.9 |
Federal | 2030 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 13.6 |
Federal | 2031 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 31.4 |
Federal | 2032 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 8.6 |
Federal | 2033 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 15.3 |
State |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 112.9 |
State | 2021 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | 17.2 |
State | 2025 |  |
Net operating loss carryforward |  |
Net operating loss carryforward | $ 95.7 |

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
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