CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL (USD $) In Millions, unless otherwise specified	Total	General Partner's Interests	Common Units	Class B Common Units
Partners' capital at Dec. 31, 2012	$ 271.8	$ 32.3	$ 238.3	$ 1.2
Increase (Decrease) in Partners' Capital
Net earnings	166.8	73.0	92.2	1.6
Distributions	(118.0)	(49.5)	(67.3)	(1.2)
Partners' capital at Mar. 31, 2013	320.6	55.8	263.2	1.6
Partners' capital at Dec. 31, 2013	309.0	43.0	264.5	1.5
Increase (Decrease) in Partners' Capital
Net earnings	102.9	41.5	60.4	1.0
Distributions	(61.1)	(21.7)	(38.8)	(0.6)
Partners' capital at Mar. 31, 2014	$ 350.8	$ 62.8	$ 286.1	$ 1.9