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Number of securities in unrealized loss position.

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Number of trust preferred securities.

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

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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 of unrealized loss on securities classified as available-for-sale.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Investment Securities - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015 Segment Security	Mar. 31, 2014	Dec. 31, 2014
Investment [Line Items]
Trading securities that consist of mutual funds	$ 3,964,000us-gaap_TradingSecurities	$ 3,681,000us-gaap_TradingSecurities	$ 3,881,000us-gaap_TradingSecurities
Number of segments	2us-gaap_NumberOfReportableSegments
Other-than-temporary-impairment losses on securities	0	100,000
Number of securities in security portfolio	1,788
Number of securities in unrealized loss position	120
Unrealized losses	24,144,000		34,606,000
Other than temporary impairment losses		100,000us-gaap_ImpairmentOfInvestments
Other than temporary impairment losses on pooled trust preferred securities		100,000
Former Directors and Executives of Monroe Bancorp [Member]
Investment [Line Items]
Trading securities that consist of mutual funds	4,000,000		3,900,000
Pooled Trust Preferred Securities, Not Subject to FASB ASC 325-10 [Member]
Investment [Line Items]
Number of trust preferred securities	2
Securities portfolio at fair value	6,400,000
Unrealized losses	7,600,000
Pooled Trust Preferred Securities, Subject To FASB ASC 325-10 [Member]
Investment [Line Items]
Number of trust preferred securities	1
Securities portfolio at fair value	200,000
Unrealized losses	3,500,000
Pooled Trust Preferred Securities [Member]
Investment [Line Items]
Number of trust preferred securities	3
Securities portfolio at fair value	6,600,000
Unrealized losses	11,200,000
Unrealized losses	11,153,000		11,358,000
Other than temporary impairment losses	$ 0	$ 0