Computation of Basic and Diluted Loss Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Loss from continuing operations	$ (1,873)	$ (3,155)	$ (4,035)	$ (2,516)
Loss from discontinued operations, net of income taxes	(51)	(735)	(655)	(2,620)
Net loss	(1,924)	(3,890)	(4,690)	(5,136)
Loss attributable to noncontrolling interest
Net loss attributable to Signature Group Holdings, Inc.	$ (1,924)	$ (3,890)	$ (4,690)	$ (5,136)
Weighted-average basic and diluted shares outstanding	118,325,427	115,651,953	118,231,543	115,019,975
Basic and diluted loss per share:
Continuing operations	$ (0.02)	$ (0.03)	$ (0.03)	$ (0.02)
Discontinued operations		$ (0.01)	$ (0.01)	$ (0.02)
Basic and diluted loss per share	$ (0.02)	$ (0.04)	$ (0.04)	$ (0.04)

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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- Definition

The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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No definition available.

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount 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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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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No definition available.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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No definition available.

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