RETIREMENT PLANS: (Tables)

12 Months Ended

Dec. 31, 2016

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs

Net periodic benefit cost and other amounts recognized in other comprehensive income included the following components:

(Dollar amounts in thousands)	2016			2015			2014
Service cost - benefits earned	$	1,882		$	2,153		$	2,040
Interest cost on projected benefit obligation	3,729			3,516			3,756
Loss due to settlement	—			—			2,676
Expected return on plan assets	(3,429		)	(3,452		)	(3,794		)
Net amortization and deferral	1,936			2,065			750
Net periodic pension cost	4,118			4,282			5,428
Net loss (gain) during the period	(6,150		)	(1,894		)	23,111
Adjustment to loss due to settlement	—			—			(2,676		)
Settlement	—			—			(7,148		)
Amortization of prior service cost	(1		)	(1		)	9
Amortization of unrecognized gain (loss)	(1,935		)	(2,064		)	(759		)
Total recognized in other comprehensive (income) loss	(8,086		)	(3,959		)	12,537
Total recognized net periodic pension cost and other comprehensive income	$	(3,968	)	$	323		$	17,965

Schedule of Defined Benefit Plans Disclosures

The information below sets forth the change in projected benefit obligation, reconciliation of plan assets, and the funded status of the Corporation's retirement program. Actuarial present value of benefits is based on service to date and present pay levels.

(Dollar amounts in thousands)	2016			2015
Change in benefit obligation:
Benefit obligation at January 1	$	90,855		$	98,135
Service cost	1,882			2,153
Interest cost	3,729			3,516
Actuarial (gain) loss	2,839			(8,802		)
Benefits paid	(6,072		)	(4,147		)
Benefit obligation at December 31	93,233			90,855
Reconciliation of fair value of plan assets:
Fair value of plan assets at January 1	60,602			62,565
Actual return on plan assets	12,418			(205		)
Employer contributions	3,184			2,389
Benefits paid	(6,072		)	(4,147		)
Fair value of plan assets at December 31	70,132			60,602
Funded status at December 31 (plan assets less benefit obligation)	$	(23,101	)	$	(30,253	)

Schedule of Assumptions Used

The accumulated benefit obligation for the defined benefit pension plan was $88.5 million and $85.1 million at year-end

2016 and 2015.

Principal assumptions used to determine pension benefit obligation at year end:	2016		2015
Discount rate	4.14	%	4.34	%
Rate of increase in compensation levels	3.00		3.00

Principal assumptions used to determine net periodic pension cost:	2016		2015
Discount rate	4.34	%	3.95	%
Rate of increase in compensation levels	3.00		3.00
Expected long-term rate of return on plan assets	6.00		6.00

Schedule of Allocation of Plan Assets

The Corporation's pension plan weighted-average asset allocation for the years 2016 and 2015 by asset category are as follows:

	Pension Plan Target Allocation	ESOP Target Allocation	Pension Percentage of Plan Assets at December 31,				ESOP Percentage of Plan Assets at December 31,
ASSET CATEGORY	2016	2016	2016		2015		2016		2015
Equity securities	25-75%	95-99%	68	%	63	%	99	%	100	%
Debt securities	0-50%	0-0%	29	%	35	%	—	%	—	%
Other	0-20%	0-5%	3	%	2	%	1	%	—	%
TOTAL			100	%	100	%	100	%	100	%

Schedule Of Fair Value Of Plan Assets

The fair value of the plan assets at December 31, 2016 and 2015, by asset category, is as follows:

			Fair Value Measurements at December 31, 2016 Using:
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Observable Inputs
(Dollar amounts in thousands)	Total		(Level 1)		(Level 2)		(Level 3)
Plan assets
Equity securities	$	51,170	$	51,170	$	—	$	—
Debt securities	11,566		—		11,566		—
Investment Funds	7,396		7,396		—		—
Total plan assets	$	70,132	$	58,566	$	11,566	$	—

			Fair Value Measurements at December 31, 2015 Using:
			Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Observable Inputs
(Dollar amounts in thousands)	Total		(Level 1)		(Level 2)		(Level 3)
Plan assets
Equity securities	$	44,052	$	44,052	$	—	$	—
Debt securities	14,264		—		14,264		—
Investment Funds	2,286		2,286		—		—
Total plan assets	$	60,602	$	46,338	$	14,264	$	—

Schedule of Expected Benefit Payments

Estimated Future Payments — The following benefit payments, which reflect expected future service, are expected:

(Dollar amounts in thousands)
2017	$	260
2018	262
2019	263
2020	270
2021	262
2022-2026	1,360

Estimated Future Payments — The following benefit payments, which reflect expected future service, are expected:

PENSION BENEFITS
(Dollar amounts in thousands)
2017	$	5,424
2018	5,540
2019	5,817
2020	5,945
2021	6,138
2022-2026	33,729

Schedule Of Weighted Average Assumptions

Weighted average assumptions at December 31:

	December 31,
	2016		2015
Discount rate	4.14	%	4.34	%
Initial weighted health care cost trend rate	5.00	%	5.00	%
Ultimate health care cost trend rate	5.00		5.00
Year that the rate is assumed to stabilize and remain unchanged	2016		2015

Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates

A one-percentage-point change in the assumed health care cost trend rates would have the following effects:

	1% Point		1% Point
(Dollar amounts in thousands)	Increase		Decrease
Effect on total of service and interest cost components	$	1	$	1
Effect on post-retirement benefit obligation	28		25

Pension Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Amounts Recognized in Other Comprehensive Income (Loss)

Amounts recognized in accumulated other comprehensive income at December 31, 2016 and 2015 consist of:

(Dollar amounts in thousands)	2016		2015
Net loss (gain)	$	21,459	$	29,544
Prior service cost (credit)	4		5
	$	21,463	$	29,549

Postretirement Health Coverage [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Defined Benefit Plans Disclosures

Post-retirement health benefit expense included the following components:

	Years Ended December 31,
(Dollar amounts in thousands)	2016			2015			2014
Service cost	$	55		$	63		$	53
Interest cost	186			173			175
Amortization of transition obligation	—			—			—
Recognized actuarial loss	—			—			—
Net periodic benefit cost	241			236			228
Net loss (gain) during the period	(144		)	(200		)	456
Amortization of prior service cost	—			—			—
Total recognized in other comprehensive income (loss)	(144		)	(200		)	456
Total recognized net periodic benefit cost and other comprehensive income	$	97		$	36		$	684

The Corporation uses a measurement date of December 31. Accrued post-retirement benefits as of December 31, 2016 and 2015 are as follows:

	December 31,
(Dollar amounts in thousands)	2016			2015
Change in benefit obligation:
Benefit obligation at January 1	$	4,383		$	4,559
Service cost	55			63
Interest cost	186			173
Plan participants' contributions	69			57
Actuarial (gain) loss	(144		)	(200		)
Benefits paid	(273		)	(269		)
Benefit obligation at December 31	$	4,276		$	4,383
Funded status at December 31	$	4,276		$	4,383

Supplemental Employee Retirement Plans, Defined Benefit

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs

The amounts recognized in other comprehensive income in the current year are as follows:

(Dollar amounts in thousands)	2016			2015			2014
Net loss (gain) during the period	$	(511	)	$	(255	)	$	932
Amortization of prior service cost	—			—			—
Amortization of unrecognized gain (loss)	(57		)	(88		)	(7		)
Total recognized in other comprehensive (income) loss	$	(568	)	$	(343	)	$	925

Schedule of Expected Benefit Payments

Estimated Future Payments — The following benefit payments, which reflect expected future service, are expected:

(Dollar amounts on thousands)
2017	$	—
2018	159
2019	312
2020	305
2021	298
2022-2026	1,409