INDEBTEDNESS (Details) (USD $)	6 Months Ended	3 Months Ended
	Jun. 30, 2012	Mar. 31, 2012 Revolving credit facility	Jun. 30, 2012 Revolving credit facility Amendment to existing credit facility	Jun. 30, 2012 Revolving credit facility Federal funds rate	Jun. 30, 2012 Revolving credit facility Eurocurrency
Long-term debt
Maximum borrowing capacity			$ 450,000,000
Maximum increase in the borrowing capacity that is available to the company, subject to certain limitations and satisfaction of certain conditions			200,000,000
Basis spread on variable rate (as a percent)				0.50%	1.00%
Write off of deferred financing fees	477,000	500,000
Debt instrument fees		$ 2,800,000