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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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Loans - Allowance for Loan Losses Disaggregated on the Basis of Impairment Methodology (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	$ 15,861		$ 17,537	$ 20,711
Loans collectively evaluated for impairment	77,539		86,916	84,937
Ending balance	93,400	93,589	104,453	105,648	107,181	110,147
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	11,330		13,171	17,983
Loans collectively evaluated for impairment	39,484		40,993	35,492
Ending balance	50,814	51,085	54,164	53,475	45,869	42,774
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment	4,531		4,366	2,728
Loans collectively evaluated for impairment	19,042		24,980	24,903
Ending balance	23,573	24,809	29,346	27,631	20,003	20,912
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment
Loans collectively evaluated for impairment	4,917		5,252	5,235
Ending balance	4,917	5,148	5,252	5,235	3,699	3,540
Consumer and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment
Loans collectively evaluated for impairment	4,130		3,507	3,649
Ending balance	4,130	3,724	3,507	3,649	8,715	12,635
Unallocated [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans individually evaluated for impairment
Loans collectively evaluated for impairment	9,966		12,184	15,658
Ending balance	$ 9,966	$ 8,823	$ 12,184	$ 15,658	$ 28,895	$ 30,286