Investment Securities - Amortized Cost and Fair Value of Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for Sale, Within one year, Amortized Cost	$ 0
Available for Sale, One to five years, Amortized Cost	0
Available for Sale, Five to ten years, Amortized Cost	0
Available for Sale, After ten years, Amortized Cost	0
Total Available for Sale, by contractual maturity, Amortized Cost	0
Available for Sale, Amortized Cost	47,634	$ 47,554
Available for Sale, Within one year, Fair Value	0
Available for Sale, One to five years, Fair Value	0
Available for Sale, Five to ten years, Fair Value	0
Available for Sale, After ten years, Fair Value	0
Total Available for Sale, by contractual maturity, Fair Value	0
Available for Sale, Fair Value	47,820	48,084
Held to Maturity Securities, Within one year, Amortized cost	360
Held to Maturity, One to five years, Amortized Cost	1,559
Held to Maturity, Five to ten years, Amortized Cost	2,262
Held to Maturity, After ten years, Amortized Cost	1,224
Total Held to Maturity, Amortized Cost	17,141	7,082
Held to Maturity Securities, Within one year, Fair Value	361
Held to Maturity, One to five years, Fair Value	1,563
Held to Maturity, Five to ten years, Fair Value	2,268
Held to Maturity, After ten years, Fair Value	1,227
Total Held to Maturity, Fair Value	17,153	7,110
Municipal Securities [Member]
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Total Held to Maturity, Amortized Cost	5,405	2,346
Total Held to Maturity, Fair Value	5,419	2,354
GSE Mortgage-Backed Pass-Through Securities [Member]
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Total Held to Maturity, Amortized Cost	11,736	4,736
Total Held to Maturity, Fair Value	11,734	4,756
Ginnie Mae and GSE Mortgage-Backed Pass-Through Securities [Member]
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for Sale, Amortized Cost	43,887	43,675
Available for Sale, Fair Value	44,068	44,198
Ginnie Mae Collateralized Mortgage Obligations [Member]
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for Sale, Amortized Cost	1,901	2,053
Available for Sale, Fair Value	1,872	2,019
Mutual Fund [Member]
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for Sale, Amortized Cost	1,846	1,826
Available for Sale, Fair Value	$ 1,880	$ 1,867

Schedule of available for sale securities and held to maturity securities.

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of held-to-maturity debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year.

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Fair value of held-to-maturity debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing after the tenth fiscal year following the latest fiscal year.

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