14. Earnings Per Unit of the Operating Partnership (Tables)

12 Months Ended

Dec. 31, 2016

Earnings per unit of the Operating Partnership [Line Items]

Schedule of basic and diluted units outstanding [Table Text Block]

The following table sets forth the reconciliation of basic and diluted average shares outstanding used in the computation of earnings per share of common stock (in thousands except for share and per share amounts):

	Twelve months ended December 31,
	2016			2015			2014
Basic and Diluted Shares Outstanding
Weighted average common shares – basic	73,003,164			65,184,013			65,486,108
Effect of dilutive securities	835,872			—			600,271
Weighted average common shares – diluted	73,839,036			65,184,013			66,086,379
Calculation of Earnings per Share – Basic
Net income (loss) attributable to common shares	$	123,965		$	(25,338	)	$	78,662
Net income allocated to unvested restricted shares	(628		)	(599		)	(484		)
Net income (loss) attributable to common shares, adjusted	123,337			(25,937		)	78,178
Weighted average common shares – basic	73,003,164			65,184,013			65,486,108
Earnings (loss) per common share – basic	$	1.69		$	(0.40	)	$	1.19
Calculation of Earnings per Share – Diluted
Net income (loss) attributable to common shares, adjusted	$	123,337		$	(25,937	)	$	78,178
Weighted average common shares – diluted	73,839,036			65,184,013			66,086,379
Earnings (loss) per common share – diluted	$	1.67		$	(0.40	)	$	1.18

Schedule of exclusions from diluted earnings per share/unit [Table Text Block]

The following table sets forth the amount of stock options and performance units that have been excluded from the calculation of diluted earnings per share (in millions):

	Twelve months ended December 31,
	2016	2015	2014
Stock Options	—	0.6	—
Performance Units	0.1	0.1	0.1

Subsidiaries [Member]

Earnings per unit of the Operating Partnership [Line Items]

Schedule of basic and diluted units outstanding [Table Text Block]

The following table sets forth the reconciliation of basic and diluted average units outstanding used in the computation of earnings per unit:

	Twelve months ended December 31,
	2016			2015			2014
Basic and Diluted Units Outstanding
Weighted average common units – basic (includes redeemable partnership units and units of general and limited partners)	87,284,564			80,599,199			81,053,127
Effect of dilutive securities	835,872			—			600,271
Weighted average common units – diluted	88,120,436			80,599,199			81,653,398
Calculation of Earnings per Unit – Basic
Net income (loss) attributable to common units	148,213			(31,331		)	97,366
Net income allocated to unvested restricted units	(628		)	(599		)	(484		)
Net income (loss) attributable to common units, adjusted	147,585			(31,930		)	96,882
Weighted average common units – basic	87,284,564			80,599,199			81,053,127
Earnings (loss) per common unit – basic	$	1.69		$	(0.40	)	$	1.19
Calculation of Earnings per Unit – Diluted
Net income (loss) attributable to common units, adjusted	147,585			(31,930		)	96,882
Weighted average common units – diluted	88,120,436			80,599,199			81,653,398
Earnings per common unit – diluted	$	1.67		$	(0.40	)	$	1.18

Schedule of exclusions from diluted earnings per share/unit [Table Text Block]

The following table sets forth the amount of stock options and performance units that have been excluded from the calculation of diluted earnings per unit (in millions):

	Twelve months ended December 31,
	2016	2015	2014
Stock Options	—	0.6	—
Performance Units	0.1	0.1	0.1