Long-Term Debt (Tables)

6 Months Ended

Jun. 30, 2011

Long-Term Debt [Abstract]

Long-term debt

	June 30,			December 31,
	2011			2010
Revolver under credit facility, bearing interest ranging from 0.81% to 3.25%*	$	487,500		$	511,000
2015 Notes, bearing interest at 6.22%		175,000			175,000
2016 Notes, bearing interest at 3.30%		100,000			—
2018 Notes, bearing interest at 4.00%		50,000			—
2019 Notes, bearing interest at 5.25%		175,000			175,000
2021 Notes, bearing interest at 4.64%		100,000			—
Tax-exempt bonds, bearing interest ranging from 0.10% to 0.42%*		39,345			39,420
Notes payable to sellers in connection with acquisitions, bearing interest at 2.50% to 10.35%*		8,874			9,159
Notes payable to third parties, bearing interest at 6.7% to 10.9%*		2,950			3,056
		1,138,669			912,635
Less — current portion		(2,693	)		(2,657	)
	$	1,135,976		$	909,978

* Interest rates in the table above represent the range of interest rates incurred during the six month period ended June 30, 2011.