MAALP Capital - Summary of Changes in Total Capital and its Components (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Partners' Capital [Roll Forward]
Dividends, Preferred Stock, Cash	$ (922)	$ (922)	$ (2,766)	$ (2,766)
M A A L P
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	6,272,507	6,479,461	6,372,170	6,573,875
Net Income Available for Common Unitholders	81,459	54,704	211,558	167,505
Other comprehensive (loss) income - derivatives instruments (cash flow hedges)	(5,973)	3,697	(15,178)	9,501
Issuance of units	140	(35)	750	(271)
Units repurchased and retired			(3,724)	(2,912)
Exercise of unit options	(204)	291	1,036	916
Units issued in exchange for redeemable units			575	1,915
Redeemable stock fair market value adjustment	(1,269)	48	(3,455)	121
Amortization of unearned compensation	3,313	2,890	11,550	9,877
Dividends, Preferred Stock, Cash	(922)	(922)	(2,766)	(2,766)
Distributions	(113,415)	(108,599)	(340,230)	(326,226)
Contribution from noncontrolling interest	955		4,305
Ending Balance	6,236,591	6,431,535	6,236,591	6,431,535
M A A L P \| Limited Partner [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	215,404	224,813	220,043	231,676
Net income	2,814	1,913	7,336	5,888
General partnership units issued in exchange for limited partnership units	(836)	(1,165)	(1,993)	(4,283)
Adjustment for limited partners' capital at redemption value	77	(139)	(61)	(226)
Distributions	(3,912)	(3,581)	(11,778)	(11,214)
Ending Balance	213,547	221,841	213,547	221,841
M A A L P \| General Partners' Capital Account [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	5,993,973	6,177,170	6,083,142	6,270,758
Net Income Allocated to General Partners	77,723	51,869	201,456	158,851
Issuance of units	140	(35)	750	(271)
Units repurchased and retired			(3,724)	(2,912)
Exercise of unit options	(204)	291	1,036	916
General partnership units issued in exchange for limited partnership units	836	1,165	1,993	4,283
Units issued in exchange for redeemable units			575	1,915
Redeemable stock fair market value adjustment	(1,269)	48	(3,455)	121
Adjustment for limited partners' capital at redemption value	(77)	139	61	226
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification				(233)
Amortization of unearned compensation	3,313	2,890	11,550	9,877
Distributions	(109,503)	(105,018)	(328,452)	(315,012)
Ending Balance	5,964,932	6,128,519	5,964,932	6,128,519
M A A L P \| Accumulated Distributions in Excess of Net Income [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	66,840	66,840	66,840	66,840
Net income	922	922	2,766	2,766
Dividends, Preferred Stock, Cash	(922)	(922)	(2,766)	(2,766)
Ending Balance	66,840	66,840	66,840	66,840
M A A L P \| AOCI Attributable to Noncontrolling Interest [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	(9,366)	8,332	(161)	2,295
Other comprehensive (loss) income - derivatives instruments (cash flow hedges)	(5,973)	3,697	(15,178)	9,501
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification				233
Ending Balance	(15,339)	12,029	(15,339)	12,029
M A A L P \| Noncontrolling Interests-Consolidated Real Estate Entities [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance	5,656	2,306	2,306	2,306
Contribution from noncontrolling interest	955		4,305
Ending Balance	$ 6,611	$ 2,306	$ 6,611	$ 2,306

Adjustment for limited partners' capital at redemption value.

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