Earnings Per OP Unit of MAALP Earnings Per OP Unit of MAALP (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Limited Partner [Member]
Earnings Per Share Disclosure [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 65,958	$ 50,820
Dividends, Preferred Stock, Cash	$ 922	$ 922
Weighted average common units - basic	117,837	117,689
Earnings per unit - basic	$ 0.55	$ 0.42
Effect of dilutive securities	207	0
Weighted average common shares - diluted	118,044	117,689
Earnings per unit - diluted	$ 0.55	$ 0.42
Limited Partner [Member] \| Calculation of Basic Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 65,958	$ 50,820
Income from continuing operations allocated to unvested restricted shares	(87)	(79)
Dividends, Preferred Stock, Cash	(922)	(922)
Income from continuing operations available for common unitholders, adjusted	$ 64,949	$ 49,819
Earnings per unit - basic	$ 0.55	$ 0.42
Limited Partner [Member] \| Calculation of Diluted Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Income from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	$ 65,958	$ 50,820
Income from continuing operations allocated to unvested restricted shares	0	(79)
Dividends, Preferred Stock, Cash	(922)	(922)
Income from continuing operations available for common unitholders, adjusted	$ 65,036	$ 49,819
Earnings per unit - diluted	$ 0.55	$ 0.42
Parent Company [Member]
Earnings Per Share Disclosure [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 65,958	$ 50,820
Dividends, Preferred Stock, Cash	$ 922	$ 922
Effect of dilutive securities	207	0
Weighted average common shares - diluted	113,933	113,507
Restricted Stock [Member] \| Parent Company [Member]
Earnings Per Share Disclosure [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		200

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