Condensed Consolidated Statements Of Partners' Capital (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Statement of Partners' Capital [Abstract]
Partners' capital, January 1, units	88,690,985	81,203,000
Partners' capital, January 1, value	$ 1,097,737	$ 916,495
Net income	29,775	22,846
Cash distributions	47,453	39,390
Partners' capital, March 31, units	88,690,985	81,203,000
Partners' capital, March 31, value	$ 1,080,059	$ 899,951