Commitments and Contingencies (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingencies
Annual expense under non-cancelable operating lease agreements and long-term propane storage agreement	$ 20,800,000	$ 15,000,000	$ 18,400,000
Minimum future payments under non-cancelable operating lease agreements and long-term propane storage agreement
2013	18,544,000
2014	15,994,000
2015	13,825,000
2016	13,761,000
2017	14,231,000
2018 and thereafter	75,231,000
Total	151,586,000
SMR Product Supply Agreement, Future Minimum Payments, Net Minimum Payments
2013	17,412,000
2014	17,412,000
2015	17,412,000
2016	17,412,000
2017	17,412,000
2018 and thereafter	212,617,000
Total minimum payments	299,677,000
Less: Services element	114,634,000
Less: Interest	93,192,000
Less: Current portion of SMR Liability	2,259,000
Long-term portion of SMR Liability	$ 89,592,000