SHAREHOLDERS EQUITY - Dividend payments made (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders' Equity Note [Abstract]
Record Date	Dec. 10, 2012	Sep. 17, 2012	Jun. 18, 2012	Mar. 19, 2012	Dec. 05, 2011	Aug. 19, 2011	May 23, 2011	Mar. 17, 2011			Mar. 18, 2010
Payment Date	Dec. 17, 2012	Sep. 24, 2012	Jun. 25, 2012	Mar. 26, 2012	Dec. 19, 2011	Aug. 26, 2011	May 31, 2011	Mar. 24, 2011			Mar. 25, 2010
Dividends paid, per share (in dollars per share)	$ 0.13	$ 0.13	$ 0.13	$ 0.13	$ 0.12	$ 0.12	$ 0.12	$ 0.12	$ 0.52	$ 0.48	$ 0.10
Dividend paid, amount	$ 1,447	$ 1,439	$ 1,439	$ 1,437	$ 1,336	$ 1,365	$ 1,429	$ 1,415	$ 5,762	$ 5,545	$ 1,163