STOCK-BASED COMPENSATION PLANS (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Additional information
Stock-based compensation expense	$ 1,400,000	$ 1,100,000
Non-vested Stock Awards
Non-vested Stock Awards Outstanding, Number of Shares
Balance at the beginning of the period (in shares)	216
Granted (in shares)	108
Stock awards vested (in shares)	(68)	(66)
Forfeited (in shares)	(8)
Balance at the end of the period (in shares)	248
Non-vested Stock Awards Outstanding, Weighted-Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 19.88
Granted (in dollars per share)	$ 23.76
Stock awards vested (in dollars per share)	$ 19.44
Forfeited (in dollars per share)	$ 21.38
Balance at the end of the period (in dollars per share)	$ 21.67
Stock Options
Stock Options Outstanding, Number of Shares
Balance at the beginning of the period (in shares)	409
Stock options exercised (in shares)	(18)
Expired (in shares)	(19)
Balance at the end of the period (in shares)	372
Exercisable options at the end of the period (in shares)	372
Stock Options Outstanding, Weighted-Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 25.68
Stock options exercised (in dollars per share)	$ 21.04
Expired (in dollars per share)	$ 22.83
Balance at the end of the period (in dollars per share)	$ 25.93
Exercisable options at the end of the period (in dollars per share)	$ 25.93
Additional information
Proceeds from stock option exercises	$ 376,000	$ 624,000