Securities Available-for Sale - Summary Available-for-Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 8,599	$ 6,632
Gross Unrealized Gains	51	38
Gross Unrealized Losses	(9)	(34)
Fair Value	8,641us-gaap_AvailableForSaleSecurities	6,636us-gaap_AvailableForSaleSecurities
U.S. Government-Sponsored Entities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,000	6,000
Gross Unrealized Gains	15
Gross Unrealized Losses	(9)	(34)
Fair Value	8,006	5,966
Residential Mortgage-Backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	599	632
Gross Unrealized Gains	36	38
Fair Value	$ 635	$ 670

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

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-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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-Publisher FASB

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity 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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