STOCK-BASED COMPENSATION PLAN (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of options granted (in shares)			0	0	0
Fair Value Per Share (in USD per share)		$ 26.89	$ 24.40	$ 24.40		$ 26.89
Expected volatility, measurement period			3 years
Net Expense			$ 1,681	$ 1,746	$ 2,764
Capitalized			$ (216)	$ (147)	(237)
Unrecognized compensation cost of awards granted under the plan						$ 2,900
Weighted average period over which unrecognized compensation cost is to be recognized (in years)			1 year 9 months 18 days
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 26.89	$ 24.40
Granted (in USD per share)			28.67
Vested (in USD per share)	[1]		24.57
Cancelled/Forfeited (in USD per share)	[2]		26.56
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 26.89	$ 24.40
Cost [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Net Expense			$ 1,897	$ 1,893	$ 3,001
EPS [Member] | Cost [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Net Expense			$ (1,200)	$ (1,100)
Officers and Key Employees [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of awards granted (in shares)			158,929	136,526	112,928
Vesting period of shares (in shares)			3 years
The range of the actual amount of shares that ultimately vest of the original share units granted (in hundredths)			0% to 200%
Actual amount of shares that ultimately vest of the original share units granted, minimum			0.00%
Actual amount of shares that ultimately vest of the original share units granted, maximum			200.00%
Shares Outstanding (in shares)		226,191	223,876	223,876		226,191
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		226,191	223,876
Granted (in shares)			158,929	136,526	112,928
Vested (in shares)	[1]		(91,244)
Cancelled/Forfeited (in shares)	[2]		(65,370)
Nonvested Shares Outstanding, ending balance (in shares)			226,191	223,876
Weighted Average Fair Value
Number of shares awarded during the period (in shares)			0	0	66,077
Market value of shares awarded (in shares)					$ 3,300
Officers and Key Employees [Member] | Forecast [Member]
Weighted Average Fair Value
Number of shares awarded during the period (in shares)		0
Officers and Key Employees [Member] | Cost [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Net Expense			$ 1,128	$ 1,260	2,236
Officers and Key Employees [Member] | 2014 - TSR [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)		51,349	51,349			51,349
Fair Value Per Share (in USD per share)		$ 21.31	$ 21.31			$ 21.31
Expected Volatility			20.00%
Risk-Free Interest Rate			0.80%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		51,349
Nonvested Shares Outstanding, ending balance (in shares)			51,349
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 21.31
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 21.31
Officers and Key Employees [Member] | 2014 - EPS [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)		51,349	51,349			51,349
Fair Value Per Share (in USD per share)		$ 27.22	$ 27.22			$ 27.22
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		51,349
Nonvested Shares Outstanding, ending balance (in shares)			51,349
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 27.22
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 27.22
Officers and Key Employees [Member] | 2015 -TSR [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)		34,574	34,574			34,574
Fair Value Per Share (in USD per share)		$ 26.31	$ 26.31			$ 26.31
Expected Volatility			16.00%
Risk-Free Interest Rate			1.10%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		34,574
Nonvested Shares Outstanding, ending balance (in shares)			34,574
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 26.31
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 26.31
Officers and Key Employees [Member] | 2015- EPS, ROE, Time [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)		88,919	88,919			88,919
Fair Value Per Share (in USD per share)		$ 29.47	$ 29.47			$ 29.47
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		88,919
Nonvested Shares Outstanding, ending balance (in shares)			88,919
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 29.47
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 29.47
Directors [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of awards granted (in shares)			26,338
Vesting period of shares (in shares)			12 months
Shares Outstanding (in shares)		26,338	23,220	23,220		26,338
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		26,338	23,220
Granted (in shares)			26,338
Vested (in shares)	[1]		(23,220)
Cancelled/Forfeited (in shares)	[2]		0
Nonvested Shares Outstanding, ending balance (in shares)			26,338	23,220
Weighted Average Fair Value
Market value of shares awarded (in shares)			$ 800	$ 600	600
Directors [Member] | Cost [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Net Expense			$ 769	$ 633	$ 765
Directors [Member] | 2015 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)		26,338	26,338			26,338
Fair Value Per Share (in USD per share)		$ 29.21	$ 29.21			$ 29.21
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)		26,338
Nonvested Shares Outstanding, ending balance (in shares)			26,338
Weighted Average Fair Value
Nonvested Shares Outstanding, beginning balance (in USD per share)		$ 29.21
Nonvested Shares Outstanding, ending balance (in USD per share)			$ 29.21
Stock Appreciation Rights (SARs) [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of awards granted (in shares)			0	0	0
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Granted (in shares)			0	0	0
Restricted Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Return on equity award threshold			7.00%
Restricted Stock [Member] | Officers and Key Employees [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of awards granted (in shares)			47,678
Vesting period of shares (in shares)			3 years
Payout limit, percentage			100.00%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Granted (in shares)			47,678
Restricted Stock [Member] | Directors [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of awards granted (in shares)			26,338	23,220	24,570
Percent of shares vested, Directors						100.00%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Granted (in shares)			26,338	23,220	24,570

[1] *

[2] Represents shares forfeited as a result of retirements prior to the satisfaction of service conditions.