Earnings Per OP Unit of MAALP Earnings Per OP Unit of MAALP (Details) - Limited Partner [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share Disclosure [Line Items]
Weighted average common units - basic	117,783	117,619	117,754	117,589
Effect of dilutive securities	207	211	174	279
Weighted average common shares - diluted	117,990	117,830	117,928	117,868
Dividends, Preferred Stock, Cash			$ 1,844	$ 1,844
Earnings per unit - basic	$ 0.52	$ 0.42	$ 0.94	$ 0.78
Earnings per unit - diluted	$ 0.52	$ 0.42	$ 0.94	$ 0.78
Calculation of Basic Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Income from continuing operations	$ 61,981	$ 50,155	$ 112,801	$ 93,571
Income from continuing operations allocated to unvested restricted shares	(78)	(76)	(142)	(149)
Dividends, Preferred Stock, Cash	(922)	(922)	(1,844)	(1,844)
Income from continuing operations available for common unitholders, adjusted	$ 60,981	$ 49,157	$ 110,815	$ 91,578
Earnings per unit - basic	$ 0.52	$ 0.42	$ 0.94	$ 0.78
Calculation of Diluted Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Income from continuing operations	$ 61,981	$ 50,155	$ 112,801	$ 93,571
Dividends, Preferred Stock, Cash	(922)	(922)	(1,844)	(1,844)
Income from continuing operations available for common unitholders, adjusted	$ 61,059	$ 49,233	$ 110,957	$ 91,727
Earnings per unit - diluted	$ 0.52	$ 0.42	$ 0.94	$ 0.78