ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Balance at beginning of period	$ 1,250		$ (4,375)		$ 155		$ (2,807)
Other comprehensive income (loss) before reclassification	(849)		864		391		(1,170)
Amounts reclassified from accumulated other comprehensive income	87		234		(58)		700
Net current period other comprehensive income (loss)	(762)		1,098		333		(470)
Balance at end of period	488		(3,277)		488		(3,277)
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net gains on securities transactions	0		0		522		1
Pension and other employee benefits	1,294		1,372		4,132		4,161
Income tax expense (benefit)	(621)		1,002		1,199		3,479
Net of tax	(319)		2,179		3,676		7,246
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(87)		(234)		58		(700)
Unrealized Gains and Losses on Securities Available for Sale [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Balance at beginning of period	6,962		5,988		6,043		8,023
Other comprehensive income (loss) before reclassification	(849)		864		391		(1,170)
Amounts reclassified from accumulated other comprehensive income	0		0		(321)		(1)
Net current period other comprehensive income (loss)	(849)		864		70		(1,171)
Balance at end of period	6,113		6,852		6,113		6,852
Unrealized Gains and Losses on Securities Available for Sale [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Total impairment losses	0		0		0		0
Net gains on securities transactions	0		0		522		1
Income tax expense (benefit)	0		0		201		0
Net of tax	0		0		321		1
Defined Benefit and Other Benefit Plans [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Balance at beginning of period	(5,712)		(10,363)		(5,888)		(10,830)
Other comprehensive income (loss) before reclassification	0		0		0		0
Amounts reclassified from accumulated other comprehensive income	87		234		263		701
Net current period other comprehensive income (loss)	87		234		263		701
Balance at end of period	(5,625)		(10,129)		(5,625)		(10,129)
Defined Benefit and Other Benefit Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income tax expense (benefit)	60		146		170		438
Net of tax	(87)		(234)		(263)		(701)
Prior Service Costs [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Pension and other employee benefits	22	[1]	21	[1]	66	[1]	63	[1]
Actuarial Losses [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Pension and other employee benefits	$ (169)	[1]	$ (401)	[1]	$ (499)	[1]	$ (1,202)	[1]

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension and other benefit plan costs (see Note 9 for additional information).