COMMON STOCK (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Common Stock [Roll Forward]
Beginning balance (in shares)			31,653,262
New issues during period [Abstract]
Dividend reinvestment plan (in shares)			231,485
Stock-based compensation plan (in shares)			78,363
Ending balance (in shares)	31,963,110		31,963,110
Par value of common stock (in dollars per share)	$ 1.25		$ 1.25
Net excess over par value recorded in premium on common stock			$ 13,600,000
Incremental shares included in diluted earnings per share (in shares)	63,174	79,355	58,374	76,313
Proceeds from sale of common stock			$ 12,502,000	$ 9,256,000