ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Reclassification Adjustments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Provision for income taxes	$ 1,434	$ 1,042
Pension Plan.
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Net of tax, increase to net income	72	75
Reclassification adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Total reclassification adjustments	(94)	75
Reclassification adjustments \| Unrealized Gains (Losses) on Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Net losses (gains) on investment securities	(255)
Total before tax	(255)
Provision for income taxes	89
Net of tax, increase to net income	(166)
Reclassification adjustments \| Pension Plan.
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Compensation and benefits	110	116
Total before tax	110	116
Provision for income taxes	(38)	(41)
Net of tax, decrease to net income	$ 72	$ 75

Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

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