Income Taxes (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred Tax Assets
Deferred gain on disposal of businesses	$ 23,672	$ 21,883
Investments, net	45,270	48,551
Deferred acquisition costs	11,687	13,466
Compensation related	1,150	1,598
Employee and post-retirement benefits	3,553	1,642
Total deferred tax asset	85,332us-gaap_DeferredTaxAssetsGross	87,140us-gaap_DeferredTaxAssetsGross
Deferred Tax Liabilities
Net unrealized appreciation on securities	(154,852)	(99,002)
Policyholder and separate account reserves	(4,848)	(2,058)
Accrued liabilities	(1,938)	(1,934)
Other	(5,147)us-gaap_DeferredTaxLiabilitiesOther	(6,388)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liability	(166,785)us-gaap_DeferredIncomeTaxLiabilities	(109,382)us-gaap_DeferredIncomeTaxLiabilities
Net deferred income tax liability	(81,453)usic_DeferredTaxLiabilitiesAssets	(22,242)usic_DeferredTaxLiabilitiesAssets
Net operating or capital loss carryforwards	0
Cumulative valuation allowance against deferred tax assets	$ 0

Amount of deferred tax liability attributable to taxable temporary differences.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Liability

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