Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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.

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Finance Receivables and Allowance for Credit Losses - Schedule of Activity in Allowance for Loan Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Charge-offs									$ (100)	$ (200)
Provision	869us-gaap_ProvisionForLoanAndLeaseLosses	2,591us-gaap_ProvisionForLoanAndLeaseLosses	(400)us-gaap_ProvisionForLoanAndLeaseLosses	37us-gaap_ProvisionForLoanAndLeaseLosses	2,253us-gaap_ProvisionForLoanAndLeaseLosses	(1,724)us-gaap_ProvisionForLoanAndLeaseLosses	(3,693)us-gaap_ProvisionForLoanAndLeaseLosses	845us-gaap_ProvisionForLoanAndLeaseLosses	3,097us-gaap_ProvisionForLoanAndLeaseLosses	(2,319)us-gaap_ProvisionForLoanAndLeaseLosses	5,030us-gaap_ProvisionForLoanAndLeaseLosses
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				16,565				14,642	16,565	14,642	19,964
Charge-offs									(3,396)	(3,810)	(7,636)
Recoveries									2,986	4,098	5,166
Provision									4,515	1,635	(2,852)
Ending balance	20,670				16,565				20,670	16,565	14,642
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				22,401				31,289	22,401	31,289	26,993
Charge-offs									(2,352)	(5,427)	(4,386)
Recoveries									2,576	2,963	5,104
Provision									(5,277)	(6,424)	3,578
Ending balance	17,348				22,401				17,348	22,401	31,289
Consumer Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				4,940				5,155	4,940	5,155	6,954
Charge-offs									(4,675)	(6,279)	(8,094)
Recoveries									3,056	4,333	3,259
Provision									3,548	1,731	3,036
Ending balance	6,869				4,940				6,869	4,940	5,155
Residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				3,239				3,677	3,239	3,677	4,149
Charge-offs									(793)	(1,487)	(2,204)
Recoveries									205	310	464
Provision									311	739	1,268
Ending balance	2,962				3,239				2,962	3,239	3,677
Loans and Leases Receivable Allowance [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				47,145				54,763	47,145	54,763	58,060
Charge-offs									(11,216)	(17,003)	(22,320)
Recoveries									8,823	11,704	13,993
Provision									3,097	(2,319)	5,030
Ending balance	$ 47,849				$ 47,145				$ 47,849	$ 47,145	$ 54,763