Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Supplemental Cash Flow Information [Abstract]
Cash paid during the period for interest	$ 19,292		$ 18,091
Change in accrued capital expenditures	3,214		889
Amortization of increasing rate distributions	$ 3,988	[1]	$ 3,829	[1]

[1] Amortization of increasing rate distributions is offset in the preferred unitholders’ capital account by a non-cash distribution