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Allowance to loans acquired with deteriorated credity quality ratio.

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Financing Receivable, Allowance for Credit Losses, Net Charge Offs

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Percentage of credit loss allowance to loans for loans collectively evaluated for impairment.

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No definition available.

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Percentage of credit loss allowance for loans specifically evaluated for impairment.

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No definition available.

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Amount of addition to allowance reserve for credit loss arising from purchase of loan and lease portfolios.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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The amount of any significant purchases of financing receivables during the reporting period.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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CREDIT QUALITY ASSESSMENT (Activity in Allowance for Loan and Lease Losses by Respective Loan Portfolio Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 45,257	$ 44,067	$ 44,067
Provision (credit)	$ 1,733	$ 1,322	3,730	1,516	2,977
Charge-offs			(818)	(824)	(2,566)
Recoveries			324	320	779
Net charge-offs			(494)	(504)	(1,787)
Balance at period end	48,493	$ 45,079	48,493	45,079	45,257
Total loans and leases	$ 6,250,073		$ 6,250,073		$ 4,314,248
Allowance for loans and leases to total loans and leases ratio	0.78%		0.78%		1.05%
Balance of loans specifically evaluated for impairment	$ 18,897		$ 18,897		$ 20,809
Allowance for loans specifically evaluated for impairment	$ 4,503		$ 4,503		$ 4,014
Specific allowance to specific loans ratio	23.83%		23.83%		19.29%
Balance of loans collectively evaluated	$ 6,202,906		$ 6,202,906		$ 4,293,439
Allowance for loans collectively evaluated	43,990		$ 43,990		$ 41,243
Collective allowance to collective loans ratio			0.71%		0.96%
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 28,270
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Commercial
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 8,711	7,539	$ 7,539
Provision (credit)			1,033		2,616
Charge-offs			(378)		(1,538)
Recoveries			129		94
Net charge-offs			(249)		(1,444)
Balance at period end	9,495		9,495		8,711
Total loans and leases	$ 702,939		$ 702,939		$ 497,948
Allowance for loans and leases to total loans and leases ratio	1.35%		1.35%		1.75%
Balance of loans specifically evaluated for impairment	$ 7,668		$ 7,668		$ 8,105
Allowance for loans specifically evaluated for impairment	$ 3,123		$ 3,123		$ 3,220
Specific allowance to specific loans ratio	40.73%		40.73%		39.73%
Balance of loans collectively evaluated	$ 688,133		$ 688,133		$ 489,843
Allowance for loans collectively evaluated	6,372		$ 6,372		$ 5,491
Collective allowance to collective loans ratio			0.93%		1.12%
Commercial \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 7,138
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Consumer
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 2,383	2,828	$ 2,828
Provision (credit)			327		(57)
Charge-offs			(414)		(693)
Recoveries			71		305
Net charge-offs			(343)		(388)
Balance at period end	2,367		2,367		2,383
Total loans and leases	$ 525,574		$ 525,574		$ 455,829
Allowance for loans and leases to total loans and leases ratio	0.45%		0.45%		0.52%
Balance of loans collectively evaluated	$ 524,231		$ 524,231		$ 455,829
Allowance for loans collectively evaluated	2,367		$ 2,367		$ 2,383
Collective allowance to collective loans ratio			0.45%		0.52%
Consumer \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 1,343
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 3,501	4,652	$ 4,652
Provision (credit)			688		(1,254)
Charge-offs			0		0
Recoveries			62		103
Net charge-offs			62		103
Balance at period end	4,251		4,251		3,501
Total loans and leases	$ 609,266		$ 609,266		$ 292,443
Allowance for loans and leases to total loans and leases ratio	0.70%		0.70%		1.20%
Balance of loans specifically evaluated for impairment	$ 136		$ 136		$ 136
Allowance for loans specifically evaluated for impairment	$ 0		$ 0		$ 0
Specific allowance to specific loans ratio	0.00%		0.00%		0.00%
Balance of loans collectively evaluated	$ 609,130		$ 609,130		$ 292,307
Allowance for loans collectively evaluated	4,251		$ 4,251		$ 3,501
Collective allowance to collective loans ratio			0.70%		1.20%
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 0
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 14,970	12,939	$ 12,939
Provision (credit)			2,000		1,930
Charge-offs			0		0
Recoveries			16		101
Net charge-offs			16		101
Balance at period end	16,986		16,986		14,970
Total loans and leases	$ 1,923,827		$ 1,923,827		$ 1,112,710
Allowance for loans and leases to total loans and leases ratio	0.88%		0.88%		1.35%
Balance of loans specifically evaluated for impairment	$ 5,878		$ 5,878		$ 5,575
Allowance for loans specifically evaluated for impairment	$ 1,255		$ 1,255		$ 663
Specific allowance to specific loans ratio	21.35%		21.35%		11.89%
Balance of loans collectively evaluated	$ 1,900,464		$ 1,900,464		$ 1,107,135
Allowance for loans collectively evaluated	15,731		$ 15,731		$ 14,307
Collective allowance to collective loans ratio			0.83%		1.29%
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 17,485
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 7,178	7,885	$ 7,885
Provision (credit)			(740)		(459)
Charge-offs			0		(248)
Recoveries			0		0
Net charge-offs			0		(248)
Balance at period end	6,438		6,438		7,178
Total loans and leases	$ 1,184,421		$ 1,184,421		$ 857,196
Allowance for loans and leases to total loans and leases ratio	0.54%		0.54%		0.84%
Balance of loans specifically evaluated for impairment	$ 3,440		$ 3,440		$ 4,078
Allowance for loans specifically evaluated for impairment	$ 125		$ 125		$ 131
Specific allowance to specific loans ratio	3.63%		3.63%		3.21%
Balance of loans collectively evaluated	$ 1,178,689		$ 1,178,689		$ 853,118
Allowance for loans collectively evaluated	6,313		$ 6,313		$ 7,047
Collective allowance to collective loans ratio			0.54%		0.83%
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 2,292
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 7,268	7,261	$ 7,261
Provision (credit)			(144)		(56)
Charge-offs			(26)		(87)
Recoveries			35		150
Net charge-offs			9		63
Balance at period end	7,133		7,133		7,268
Total loans and leases	$ 1,106,674		$ 1,106,674		$ 921,435
Allowance for loans and leases to total loans and leases ratio	0.64%		0.64%		0.79%
Balance of loans specifically evaluated for impairment	$ 1,775		$ 1,775		$ 2,915
Allowance for loans specifically evaluated for impairment	0		0		0
Balance of loans collectively evaluated	1,104,887		1,104,887		918,520
Allowance for loans collectively evaluated	7,133		$ 7,133		$ 7,268
Collective allowance to collective loans ratio			0.65%		0.79%
Residential Real Estate Portfolio Segment \| Residential Mortgage \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 12
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%
Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 1,246	$ 963	$ 963
Provision (credit)			566		257
Charge-offs			0		0
Recoveries			11		26
Net charge-offs			11		26
Balance at period end	1,823		1,823		1,246
Total loans and leases	$ 197,372		$ 197,372		$ 176,687
Allowance for loans and leases to total loans and leases ratio	0.92%		0.92%		0.71%
Balance of loans specifically evaluated for impairment	$ 0		$ 0		$ 0
Allowance for loans specifically evaluated for impairment	0		0		0
Balance of loans collectively evaluated	197,372		197,372		176,687
Allowance for loans collectively evaluated	$ 1,823		$ 1,823		$ 1,246
Collective allowance to collective loans ratio			0.92%		0.71%
Residential Real Estate Portfolio Segment \| Residential Construction \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance of loans acquired			$ 0
Allowance for loans acquired			$ 0
Allowance to loans acquired with deteriorated credity quality ratio			0.00%