OTHER COMPREHENSIVE INCOME : OTHER COMPREHENSIVE INCOME (LOSS)-Reclassifications (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains (losses)									$ 423		$ 886		$ 6
Income tax expense									(13,767)		(13,818)		(14,397)
NET INCOME	8,923	8,472	6,446	7,693	8,573	8,091	8,705	7,443	31,534		32,812		37,195
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
NET INCOME									(10,315)		(1,799)
Unrealized Gains and Losses on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains (losses)									423		886
Income tax expense									(169)		(354)
NET INCOME									254		532
Retirement Plans | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Change in funded status of post retirement benefits									(17,615)	[1]	(3,885)	[1]
Income tax expense									7,046		1,554
NET INCOME									$ (10,569)		$ (2,331)

[1] Included in the computation of net periodic benefit cost which is included in salaries and benefits. (see Footnote 15 for additional details).