UNAUDITED CONDENSED STATEMENTS OF CONSOLIDATED EQUITY - USD ($) $ in Millions	Total	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]	Limited Partners [Member]
Balance at Dec. 31, 2017	$ 22,772.4	$ (171.7)	$ 225.2	$ 22,718.9
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	1,598.7	0.0	24.2	1,574.5
Cash distributions paid to limited partners	(1,847.3)	0.0	0.0	(1,847.3)
Cash payments made in connection with distribution equivalent rights	(8.6)	0.0	0.0	(8.6)
Cash distributions paid to noncontrolling interests	(28.3)	0.0	(28.3)	0.0
Cash contributions from noncontrolling interests	206.9	0.0	206.9	0.0
Net cash proceeds from the issuance of common units	261.0	0.0	0.0	261.0
Common units issued in connection with employee compensation	39.1	0.0	0.0	39.1
Common units issued in connection with land acquisition	30.0	0.0	0.0	30.0
Amortization of fair value of equity-based awards	52.6	0.0	0.0	52.6
Cash flow hedges	49.0	49.0	0.0	0.0
Other	(35.0)	(0.5)	(9.1)	(25.4)
Balance at Jun. 30, 2018	23,090.5	(123.2)	418.9	22,794.8
Balance at Mar. 31, 2018	22,964.9	(161.2)	211.6	22,914.5
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	687.2	0.0	13.4	673.8
Cash distributions paid to limited partners	(928.8)	0.0	0.0	(928.8)
Cash payments made in connection with distribution equivalent rights	(4.7)	0.0	0.0	(4.7)
Cash distributions paid to noncontrolling interests	(12.9)	0.0	(12.9)	0.0
Cash contributions from noncontrolling interests	206.8	0.0	206.8	0.0
Net cash proceeds from the issuance of common units	84.0	0.0	0.0	84.0
Common units issued in connection with land acquisition	30.0	0.0	0.0	30.0
Amortization of fair value of equity-based awards	26.6	0.0	0.0	26.6
Cash flow hedges	38.5	38.5	0.0	0.0
Other	(1.1)	(0.5)	0.0	(0.6)
Balance at Jun. 30, 2018	23,090.5	(123.2)	418.9	22,794.8
Balance at Dec. 31, 2018	24,292.2	50.9	438.7	23,802.6
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	2,516.9	0.0	41.7	2,475.2
Cash distributions paid to limited partners	(1,907.9)	0.0	0.0	(1,907.9)
Cash payments made in connection with distribution equivalent rights	(10.5)	0.0	0.0	(10.5)
Cash distributions paid to noncontrolling interests	(46.9)	0.0	(46.9)	0.0
Cash contributions from noncontrolling interests	99.6	0.0	99.6	0.0
Net cash proceeds from the issuance of common units	82.2	0.0	0.0	82.2
Common units issued in connection with employee compensation	45.6	0.0	0.0	45.6
Amortization of fair value of equity-based awards	70.5	0.0	0.0	70.5
Repurchase of common units under 2019 Buyback Program	(81.1)	0.0	0.0	(81.1)
Cash flow hedges	(61.0)	(61.0)	0.0	0.0
Other	(24.2)	(0.6)	2.5	(26.1)
Balance at Jun. 30, 2019	24,975.4	(10.7)	535.6	24,450.5
Balance at Mar. 31, 2019	24,521.3	(94.0)	463.4	24,151.9
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	1,236.5	0.0	21.8	1,214.7
Cash distributions paid to limited partners	(957.5)	0.0	0.0	(957.5)
Cash payments made in connection with distribution equivalent rights	(6.0)	0.0	0.0	(6.0)
Cash distributions paid to noncontrolling interests	(28.9)	0.0	(28.9)	0.0
Cash contributions from noncontrolling interests	64.8	0.0	64.8	0.0
Net cash proceeds from the issuance of common units	39.5	0.0	0.0	39.5
Amortization of fair value of equity-based awards	38.5	0.0	0.0	38.5
Repurchase of common units under 2019 Buyback Program	(29.5)	0.0	0.0	(29.5)
Cash flow hedges	83.3	83.3	0.0	0.0
Other	13.4	0.0	14.5	(1.1)
Balance at Jun. 30, 2019	$ 24,975.4	$ (10.7)	$ 535.6	$ 24,450.5