GENERAL (Details) (USD $)	3 Months Ended		0 Months Ended	1 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended
	Jun. 30, 2013 item	Jun. 30, 2012	Aug. 05, 2013 Subsequent Event	May 31, 2012 Third Stock Repurchase Program Maximum	Jun. 30, 2013 Fourth Stock Repurchase Program	Aug. 02, 2012 Fourth Stock Repurchase Program Maximum	Jun. 30, 2013 Fifth Stock Repurchase Program	May 07, 2013 Fifth Stock Repurchase Program Maximum
Nature of Operations
Number of reporting segments	1
Stock Repurchase Program
Authorized amount of repurchase of common stock				$ 35,000,000		$ 35,000,000		$ 35,000,000
Number of shares repurchased and retired under stock repurchase program					201,192
Average price of repurchased shares of stock (in dollars per share)					$ 61.16
Maximum dollar value of shares that may still be purchased under stock repurchase program							$ 35,000,000
Dividends declared (in dollars per share)	$ 0.50	$ 0.50	$ 0.50
Dividends
Dividends paid (in dollars per share)	$ 0.50	$ 0.50