Interest rate hedge agreements (Tables)

6 Months Ended

Jun. 30, 2011

Interest rate hedge agreements

Outstanding interest rate hedge agreements designated as cash flow hedges of interest rate risk

Transaction Date	Effective Date	Termination Date	Interest Pay Rate		Notional Amount		Effective at June 30, 2011		Fair Value
December 2006	December 29, 2006	March 31, 2014	4.990	%	$	50,000	$	50,000	$	(5,551	)
October 2007	October 31, 2007	September 30, 2012	4.546		50,000		50,000		(2,631		)
October 2007	October 31, 2007	September 30, 2013	4.642		50,000		50,000		(4,424		)
October 2007	July 1, 2008	March 31, 2013	4.622		25,000		25,000		(1,799		)
October 2007	July 1, 2008	March 31, 2013	4.625		25,000		25,000		(1,801		)
December 2006	November 30, 2009	March 31, 2014	5.015		75,000		75,000		(8,378		)
December 2006	November 30, 2009	March 31, 2014	5.023		75,000		75,000		(8,394		)
December 2006	December 31, 2010	October 31, 2012	5.015		100,000		100,000		(6,243		)
Total							$	450,000	$	(39,221	)