ACCUMULATED OTHER COMPREHENSIVE INCOME OR LOSS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Balance at beginning of period	$ (8,785)		$ 155
Other comprehensive income before reclassification	805		544
Amounts reclassified from accumulated other comprehensive income	193		88
Net current period other comprehensive gain	998		632
Balance at end of period	(7,787)		787
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net gains on securities transactions	50		0
Pension and other employee benefits	1,729		1,359
Income tax expense	(1,126)		(951)
Net of tax	2,276		2,064
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net of tax	224		88
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	1,960		6,043
Other comprehensive income before reclassification	805		544
Amounts reclassified from accumulated other comprehensive income	(31)		0
Net current period other comprehensive gain	774		544
Balance at end of period	2,734		6,587
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
Net gains on securities transactions	50		0
Income tax expense	(19)		0
Net of tax	31		0
Defined Benefit and Other Benefit Plans [Member]
Accumulated Other Comprehensive Income Loss Net Of Tax [Roll Forward]
Balance at beginning of period	(10,745)		(5,888)
Other comprehensive income before reclassification	0		0
Amounts reclassified from accumulated other comprehensive income	224		88
Net current period other comprehensive gain	224		88
Balance at end of period	(10,521)		(5,800)
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	(137)		(55)
Net of tax	224		88
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]	(22)	[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	$ 383	[1]	$ 165	[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).