INCOME TAXES: (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Tax Expense

Income tax expense is summarized as follows:

(Dollar amounts in thousands)	2016		2015			2014
Federal:
Currently payable	$	15,514	$	9,890		$	9,388
Deferred	1,326		(774		)	2,120
	16,840		9,116			11,508
State:
Currently payable	2,857		1,426			1,928
Deferred	186		(150		)	753
	3,043		1,276			2,681
TOTAL	$	19,883	$	10,392		$	14,189

Reconciliation of Income Tax Expense

The reconciliation of income tax expense with the amount computed by applying the statutory federal income tax rate of 35% to income before income taxes is summarized as follows:

(Dollar amounts in thousands)	2016			2015			2014
Federal income taxes computed at the statutory rate	$	20,403		$	14,206		$	16,786
Add (deduct) tax effect of:
Tax exempt income	(3,992		)	(4,047		)	(4,016		)
Non-deductible insurance brokerage goodwill	1,797			—			—
ESOP dividend deduction	(47		)	(164		)	(284		)
State tax, net of federal benefit	1,978			829			1,743
Affordable housing credits	(148		)	(148		)	(148		)
Other, net	(108		)	(284		)	108
TOTAL	$	19,883		$	10,392		$	14,189

Schedule of Deferred Tax Assets and Liabilities

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and liabilities at December 31, 2016 and 2015, are as follows: 

(Dollar amounts in thousands)	2016			2015
Deferred tax assets:
Other than temporary impairment	$	5,397		$	5,411
Net unrealized losses on retirement plans	8,576			12,007
Net unrealized losses on securities available for sale	719			—
Loan loss provisions	7,318			7,755
Deferred compensation	5,881			6,257
Compensated absences	832			917
Post-retirement benefits	2,043			2,026
Deferred loss on acquisition	1,111			1,177
Other	3,119			2,887
GROSS DEFERRED ASSETS	34,996			38,437
Deferred tax liabilities:
Net unrealized gains on securities available-for-sale	—			(5,234		)
Depreciation	(2,778		)	(2,632		)
Mortgage servicing rights	(486		)	(539		)
Pensions	(65		)	(424		)
Intangibles	(3,015		)	(2,283		)
Other	(3,180		)	(2,863		)
GROSS DEFERRED LIABILITIES	(9,524		)	(13,975		)
NET DEFERRED TAX ASSETS	$	25,472		$	24,462

Reconciliation of Unrecognized Tax Benefits

Unrecognized Tax Benefits — A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:

(Dollar amounts in thousands)	2016			2015			2014
Balance at January 1	$	513		$	589		$	676
Additions based on tax positions related to the current year	288			68			72
Additions based on tax positions related to prior years	—			—			—
Reductions due to the statute of limitations	(103		)	(144		)	(159		)
Balance at December 31	$	698		$	513		$	589