ALLOWANCE FOR LOAN LOSSES: (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Ending Balance Attributable to Loans
Individually evaluated for impairment	$ 1,911	$ 3,158
Collectively evaluated for impairment	16,648	15,862
Acquired with deteriorated credit quality	280	1,048
BALANCE AT END OF YEAR	18,839	20,068	21,958	19,241
Loans
Individually evaluated for impairment	14,606	18,862
Collectively evaluated for impairment	1,767,701	1,771,562
Acquired with deteriorated credit quality	6,518	10,398
BALANCE AT END OF YEAR	1,788,825	1,800,822
Commercial
Ending Balance Attributable to Loans
Individually evaluated for impairment	1,911	3,158
Collectively evaluated for impairment	8,733	8,421
Acquired with deteriorated credit quality	271	871
BALANCE AT END OF YEAR	10,915	12,450	10,987	12,119
Loans
Individually evaluated for impairment	14,573	18,825
Collectively evaluated for impairment	1,030,949	1,020,771
Acquired with deteriorated credit quality	4,887	8,001
BALANCE AT END OF YEAR	1,050,409	1,047,597
Residential
Ending Balance Attributable to Loans
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,365	1,408
Acquired with deteriorated credit quality	9	177
BALANCE AT END OF YEAR	1,374	1,585	5,426	2,728
Loans
Individually evaluated for impairment	33	37
Collectively evaluated for impairment	468,872	481,439
Acquired with deteriorated credit quality	1,631	2,397
BALANCE AT END OF YEAR	470,536	483,873
Consumer
Ending Balance Attributable to Loans
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	4,370	3,650
Acquired with deteriorated credit quality	0	0
BALANCE AT END OF YEAR	4,370	3,650	3,879	3,889
Loans
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	267,880	269,352
Acquired with deteriorated credit quality	0	0
BALANCE AT END OF YEAR	267,880	269,352
Unallocated
Ending Balance Attributable to Loans
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	2,180	2,383
Acquired with deteriorated credit quality	0	0
BALANCE AT END OF YEAR	$ 2,180	$ 2,383	$ 1,666	$ 505

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Recorded Investment in financing receivables.

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The balance of financing receivables that were acquired with deteriorated credit quality.

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The valuation allowance for financing receivables acquired with deteriorated credit quality.

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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 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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