Indebtedness (Tables)

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Schedule of Outstanding Indebtedness

At December 31, 2016 and 2015, our outstanding indebtedness included the following (in thousands):

					December 31,
	Interest Rate at December 31, 2016			Maturity Date	2016			2015
Unsecured revolving credit facility, at LIBOR plus a premium	2.02	%		1/28/2019	$	—		$	—
5-year unsecured term loan, at LIBOR plus a premium	2.17	%		1/28/2020	200,000			200,000
7-year unsecured term loan, at LIBOR plus a premium	2.57	%		1/28/2022	200,000			200,000
Unsecured floating rate debt	2.37	%	(1)		$	400,000		$	400,000
6.25% Senior Unsecured Notes due 2016	—	%		—	$	—		$	139,104
6.25% Senior Unsecured Notes due 2017	—	%		—	—			250,000
6.65% Senior Unsecured Notes due 2018	6.65	%		1/15/2018	250,000			250,000
5.875% Senior Unsecured Notes due 2020	5.88	%		9/15/2020	250,000			250,000
5.75% Senior Unsecured Notes due 2042	5.75	%		8/1/2042	175,000			175,000
Unsecured fixed rate debt	6.13	%	(1)		$	675,000		$	1,064,104
Parkshore Plaza(2)	5.67	%		5/1/2017	$	41,275		$	41,275
1735 Market Street(3)	—	%		—	—			169,612
206 East 9th Street	5.69	%		1/5/2021	27,041			27,515
33 Stiles Lane	6.75	%		3/1/2022	2,415			2,785
97 Newberry Road	5.71	%		3/1/2026	5,903			6,375
Secured fixed rate debt	5.71	%	(1)		$	76,634		$	247,562
					$	1,151,634		$	1,711,666
Unamortized net premiums, discounts and deferred financing fees					(9,967		)	(14,550		)
					$	1,141,667		$	1,697,116

(1) Represents weighted average interest rate at December 31, 2016.

(2) The Company guarantees $3.2 million of this non-recourse loan.

(3) Interest on this loan was payable at LIBOR plus 2.625% but was fixed for the first seven years to December 1, 2016 by a cash flow hedge which set the rate at approximately 5.66%.

Schedule of Required Principal Payments on Outstanding Debt

The required principal payments due during the next five years and thereafter under all of our outstanding debt at December 31, 2016 are as follows (in thousands):

2017	$	42,675
2018	251,488
2019	1,580
2020	451,674
2021	25,982
Thereafter	378,235
	$	1,151,634