Income per Common Unit of the Operating Partnership (Tables)

9 Months Ended

Sep. 30, 2011

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
	September 30, 2011					September 30, 2010
	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	$	30,535	115,014	$	0.27	$	31,108	113,077	$	0.28
Dilutive shares for long-term compensation plans	—		766			—		696
Diluted income from continuing operations
Income from continuing operations net of noncontrolling interest	30,535		115,780	$	0.27	31,108		113,773	$	0.27
Basic income from discontinued operations
Discontinued operations net of noncontrolling interest	4,785		115,014	$	0.04	3,536		113,077	$	0.03
Dilutive shares for long-term compensation plans	—		766			—		696
Diluted income from discontinued operations
Discontinued operations net of noncontrolling interest	4,785		115,780	$	0.04	3,536		113,773	$	0.03
Basic income per common share
Net income available to common shareholders	35,320		115,014	$	0.31	34,644		113,077	$	0.31
Dilutive shares for long-term compensation plans	—		766			—		696
Diluted income per common share
Net income available to common shareholders	$	35,320	115,780	$	0.31	$	34,644	113,773	$	0.30

	For the Nine Months Ended					For the Nine Months Ended
	September 30, 2011					September 30, 2010
	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	$	89,993	114,547	$	0.78	$	85,131	112,708	$	0.76
Dilutive shares for long-term compensation plans	—		782			—		680
Diluted income from continuing operations
Income from continuing operations net of noncontrolling interest	89,993		115,329	$	0.78	85,131		113,388	$	0.75
Basic income from discontinued operations
Discontinued operations net of noncontrolling interest	59,214		114,547	$	0.52	12,509		112,708	$	0.11
Dilutive shares for long-term compensation plans	—		782			—		680
Diluted income from discontinued operations
Discontinued operations net of noncontrolling interest	59,214		115,329	$	0.51	12,509		113,388	$	0.11
Basic income per common share
Net income available to common shareholders	149,207		114,547	$	1.30	97,640		112,708	$	0.87
Dilutive shares for long-term compensation plans	—		782			—		680
Diluted income per common share
Net income available to common shareholders	$	149,207	115,329	$	1.29	$	97,640	113,388	$	0.86

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
	September 30, 2011						September 30, 2010
	Income (Numerator)			Weighted Average Units (Denominator)	Per Unit		Income (Numerator)			Weighted Average Units (Denominator)	Per Unit
Income from continuing operations net of noncontrolling interest	$	36,791					$	37,436
Less: Preferred unit distributions	(5,253		)				(5,253		)
Basic income from continuing operations
Income from continuing operations available to common unitholders	31,538			118,830	$	0.27	32,183			117,020	$	0.28
Dilutive units for long-term compensation plans	—			766			—			696
Diluted income from continuing operations
Income from continuing operations available to common unitholders	31,538			119,596	$	0.27	32,183			117,716	$	0.27
Basic income from discontinued operations
Discontinued operations	4,943			118,830	$	0.04	3,659			117,020	$	0.03
Dilutive units for long-term compensation plans	—			766			—			696
Diluted income from discontinued operations
Discontinued operations	4,943			119,596	$	0.04	3,659			117,716	$	0.03
Basic income per common unit
Income available to common unitholders	36,481			118,830	$	0.31	35,842			117,020	$	0.31
Diluted units for long-term compensation plans	—			766			—			696
Diluted income per common unit
Income available to common unitholders	$	36,481		119,596	$	0.31	$	35,842		117,716	$	0.30

	For the Nine Months Ended						For the Nine Months Ended
	September 30, 2011						September 30, 2010
	Income (Numerator)			Weighted Average Units (Denominator)	Per Unit		Income (Numerator)			Weighted Average Units (Denominator)	Per Unit
Income from continuing operations net of noncontrolling interest	$	108,767					$	103,851
Less: Preferred unit distributions	(15,759		)				(15,759		)
Basic income from continuing operations
Income from continuing operations available to common unitholders	93,008			118,437	$	0.78	88,092			116,657	$	0.76
Dilutive units for long-term compensation plans	—			782			—			680
Diluted income from continuing operations
Income from continuing operations available to common unitholders	93,008			119,219	$	0.78	88,092			117,337	$	0.75
Basic income from discontinued operations
Discontinued operations	61,209			118,437	$	0.52	12,944			116,657	$	0.11
Dilutive units for long-term compensation plans	—			782			—			680
Diluted income from discontinued operations
Discontinued operations	61,209			119,219	$	0.51	12,944			117,337	$	0.11
Basic income per common unit
Income available to common unitholders	154,217			118,437	$	1.30	101,036			116,657	$	0.87
Diluted units for long-term compensation plans	—			782			—			680
Diluted income per common unit
Income available to common unitholders	$	154,217		119,219	$	1.29	$	101,036		117,337	$	0.86