Shareholders' Equity - Summary of Option Activity under the FBR & Co. Long Term Incentive Plan (Detail) - $ / shares	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Beginning Balance	990,101	1,066,803	1,288,027
Number of Shares, Granted	0	0	0
Number of Shares, Forfeitures/Expirations	(80,651)	(13,334)	(102,802)
Number of Shares, Option Exercised	(448,657)	(63,368)	(118,422)
Number of Shares, Ending Balance	460,793	990,101	1,066,803	1,288,027
Options Exercisable, Number of Shares	460,793
Weighted-average Exercise Prices, Beginning Balance	$ 21.92	$ 21.63	$ 21.72
Weighted-average Exercise Prices, Granted	0	0	0
Weighted-average Exercise Prices, Forfeitures/Expirations	26.79	22.44	24.14
Weighted-average Exercise Prices, Option Exercised	21.49	16.87	20.34
Weighted-average Exercise Prices, Ending Balance	21.49	$ 21.92	$ 21.63	$ 21.72
Options Exercisable, Weighted-average Exercise Prices	$ 21.49
Weighted Average Remaining Contractual Life	1 year 11 months 27 days	29 days	1 month 17 days	2 years 1 month 13 days
Options Exercisable, Weighted-average Remaining Contractual Life	1 year 11 months 27 days

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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-Publisher FASB
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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