Earnings Per OP Unit of MAALP Statement (details) (Limited Partner [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Earnings Per Share Disclosure [Line Items]
Weighted average common units - basic	79,263		44,408		79,148		44,293
Effect of dilutive securities	0	[1]	0	[1]	0	[1]	53
Weighted average common shares - diluted	79,263		44,408		79,148		44,346
Calculation of Basic Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Income from continuing operations	$ 70,331		$ 16,297		$ 113,088		$ 52,734
Income from continuing operations allocated to unvested restricted shares	(130)		(14)		(209)		(46)
Income from continuing operations available for common unitholders, adjusted	70,201		16,283		112,879		52,688
Income from discontinued operations	388		29,778		6,731		64,634
Income from discontinued operations allocated to unvested restricted shares	(1)		(25)		(12)		(56)
Income from discontinued operations available for common unitholders, adjusted	387		29,753		6,719		64,578
Earnings per unit - basic	$ 0.89		$ 1.04		$ 1.51		$ 2.65
Calculation of Diluted Earnings Per Unit [Member]
Earnings Per Share Disclosure [Line Items]
Income from continuing operations	70,331		16,297		113,088		52,734
Income from continuing operations allocated to unvested restricted shares	(130)	[1]	(14)	[1]	(209)	[1]	0
Income from continuing operations available for common unitholders, adjusted	70,201		16,283		112,879		52,734
Income from discontinued operations	388		29,778		6,731		64,634
Income from discontinued operations allocated to unvested restricted shares	(1)	[1]	(25)	[1]	(12)	[1]	0
Income from discontinued operations available for common unitholders, adjusted	$ 387		$ 29,753		$ 6,719		$ 64,634
Earnings per unit - diluted	$ 0.89		$ 1.04		$ 1.51		$ 2.65

[1] (1) Dilutive securities and the related income are not included in the diluted earnings per unit calculations as they were not dilutive.