Consolidated Balance Sheets (Parenthetical)	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
General partner's interest, units issued	35,750	35,750
General partner's interest, units outstanding	35,750	35,750
Limited partners' interest, units issued	35,713,700	35,713,700
Limited partners' interest, units outstanding	35,713,700	35,713,700