Income per Common Unit of the Operating Partnership (Tables)

3 Months Ended

Mar. 31, 2013

Income Per Common Unit [Line Items]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	For the Three Months Ended					For the Three Months Ended
	March 31, 2013					March 31, 2012
	Income (Numerator)		Weighted Average Shares (Denominator)	Per Share		Income (Numerator)		Weighted Average Shares (Denominator)	Per Share
Basic income from continuing operations
Income from continuing operations net of noncontrolling interest	$	29,925	118,688	$	0.25	$	31,872	115,972	$	0.28
Dilutive shares for long-term compensation plans	—		844			—		771
Diluted income from continuing operations
Income from continuing operations net of noncontrolling interest	$	29,925	119,532	$	0.25	$	31,872	116,743	$	0.28
Basic income from discontinued operations
Discontinued operations net of noncontrolling interest	$	41,314	118,688	$	0.35	$	5,217	115,972	$	0.04
Dilutive shares for long-term compensation plans	—		844			—		771
Diluted income from discontinued operations
Discontinued operations net of noncontrolling interest	$	41,314	119,532	$	0.35	$	5,217	116,743	$	0.04
Basic income per common share
Net income available to common shareholders	$	71,239	118,688	$	0.60	$	37,089	115,972	$	0.32
Dilutive shares for long-term compensation plans	—		844			—		771
Diluted income per common share
Net income available to common shareholders	$	71,239	119,532	$	0.60	$	37,089	116,743	$	0.32

Liberty Property Limited Partnership [Member]

Income Per Common Unit [Line Items]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	For the Three Months Ended						For the Three Months Ended
	March 31, 2013						March 31, 2012
	Income (Numerator)			Weighted Average Units (Denominator)	Per Unit		Income (Numerator)			Weighted Average Units (Denominator)	Per Unit
Income from continuing operations	$	32,063					$	34,215
Less: Preferred unit distributions	(1,211		)				(5,035		)
Excess of preferred unit redemption over carrying amount	—						3,729
Basic income from continuing operations
Income from continuing operations available to common unitholders	$	30,852		122,402	$	0.25	$	32,909		119,781	$	0.28
Dilutive units for long-term compensation plans	—			844			—			771
Diluted income from continuing operations
Income from continuing operations available to common unitholders	$	30,852		123,246	$	0.25	$	32,909		120,552	$	0.28
Basic income from discontinued operations
Discontinued operations	$	42,593		122,402	$	0.35	$	5,387		119,781	$	0.04
Dilutive units for long-term compensation plans	—			844			—			771
Diluted income from discontinued operations
Discontinued operations	$	42,593		123,246	$	0.35	$	5,387		120,552	$	0.04
Basic income per common unit
Income available to common unitholders	$	73,445		122,402	$	0.60	$	38,296		119,781	$	0.32
Dilutive units for long-term compensation plans	—			844			—			771
Diluted income per common unit
Income available to common unitholders	$	73,445		123,246	$	0.60	$	38,296		120,552	$	0.32