Investment Securities - Available for Sale and Held to Maturity Investment (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	$ 303,154	$ 300,028
Gross Unrealized Gains, Available for sale	467	591
Gross Unrealized Losses, Available for sale	(4,119)	(4,933)
Estimated Fair Value, Available for sale	299,502	295,686
Amortized Cost, Held to maturity	250	250
Estimated Fair Value, Held to maturity	250	250
Amortized Cost	303,404	300,278
Gross Unrealized Gains	467	591
Gross Unrealized Losses	(4,119)	(4,933)
Estimated Fair Value	299,752	295,936
U.S. Treasury Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	3,500	2,498
Gross Unrealized Losses, Available for sale	(3)
Estimated Fair Value, Available for sale	3,497	2,498
U.S. Government Agency Mortgage-Backed Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	254,895	246,650
Gross Unrealized Gains, Available for sale	459	583
Gross Unrealized Losses, Available for sale	(2,496)	(2,575)
Estimated Fair Value, Available for sale	252,858	244,658
Trust Preferred Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	12,024	12,023
Gross Unrealized Losses, Available for sale	(1,579)	(2,172)
Estimated Fair Value, Available for sale	10,445	9,851
Collateralized Loan Obligations [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	31,474	37,471
Gross Unrealized Gains, Available for sale	8	8
Gross Unrealized Losses, Available for sale	(16)	(160)
Estimated Fair Value, Available for sale	31,466	37,319
Other Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Amortized Cost, Available for sale	1,261	1,386
Gross Unrealized Losses, Available for sale	(25)	(26)
Estimated Fair Value, Available for sale	1,236	1,360
Amortized Cost, Held to maturity	250	250
Estimated Fair Value, Held to maturity	$ 250	$ 250

Available for sale and held to maturity securities gross unrealized gains.

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Available for sale and held to maturity securities gross unrealized loss.

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This item represents the cost of securities, which are categorized as available for sale or held-to-maturity, 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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Schedule of available for sale securities and held to maturity.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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.

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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.

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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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Amount of debt and equity financial instruments classified as either held-to-maturity or available-for-sale.

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

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Fair value of investments in debt securities classified as held-to-maturity.

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