Discontinued Operations (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Gain on Sale of Loan Portfolios	$ 0	$ 1.1	$ 0	$ 12.4
Income (Loss) from Discontinued Operations before Income Taxes:
Net Gain on Sale of Loan Portfolios	0	1.1	0	12.4
Income (Loss) from Discontinued Operations before Income Taxes	2.5	1.0	2.1	13.3
Income Tax Benefit (Expense)	(1.0)	(0.3)	(0.8)	(5.3)
Income (Loss) from Discontinued Operations	1.5	0.7	1.3	8.0
Income from Discontinued Operations Per Unrestricted Share:
Basic (in dollars per share)	$ 0.03	$ 0.01	$ 0.02	$ 0.14
Diluted (in dollars per share)	$ 0.03	$ 0.01	$ 0.02	$ 0.14
Fireside [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Gain on Sale of Loan Portfolios	0	1.1	0	12.4
Income (Loss) from Discontinued Operations before Income Taxes:
Results of Operations / Change in Estimate of Retained Liabilities Arising from Discontinued Operations	0	0	0	(0.2)
Net Gain on Sale of Loan Portfolios	0	1.1	0	12.4
Unitrin Business Insurance [Member]
Income (Loss) from Discontinued Operations before Income Taxes:
Results of Operations / Change in Estimate of Retained Liabilities Arising from Discontinued Operations	$ 2.5	$ (0.1)	$ 2.1	$ 1.1

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Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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The amount of net income (loss) derived from discontinued operations during the period, net of related tax effect, per each share of common stock or unit outstanding during the reporting period.

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