Indebtedness (Tables)

12 Months Ended

Dec. 31, 2015

Debt Disclosure [Abstract]

Schedule of Outstanding Indebtedness

At December 31, 2015 and 2014, our outstanding indebtedness included the following (in thousands):

					December 31,
	Interest Rate at December 31, 2015			Maturity Date	2015			2014
Unsecured revolving credit facility, at LIBOR plus a premium	1.68	%		1/28/2019	$	—		$	—
5-year unsecured term loan, at LIBOR plus a premium	1.83	%		1/28/2020	200,000			—
7-year unsecured term loan, at LIBOR plus a premium	2.23	%		1/28/2022	200,000			—
Unsecured term loan, at LIBOR plus a premium	—	%		—	—			400,000
Unsecured floating rate debt	2.03	%	(1)		$	400,000		$	400,000
5.75% Senior Unsecured Notes due 2015	—	%		—	$	—		$	138,773
6.25% Senior Unsecured Notes due 2016	6.25	%		8/15/2016	139,104			139,104
6.25% Senior Unsecured Notes due 2017	6.25	%		6/15/2017	250,000			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	6.17	%	(1)		$	1,064,104		$	1,202,877
111 Monument Circle	—	%		—	$	—		$	116,000
225 Water Street	—	%		—	—			40,059
111 East Wacker Drive	—	%		—	—			142,666
2501 20th Place South	—	%		—	—			10,267
Parkshore Plaza	5.67	%		5/1/2017	41,275			41,275
1735 Market Street(2)	5.66	%		12/2/2019	169,612			171,498
206 East 9th Street	5.69	%		1/5/2021	27,515			27,965
1320 Main Street	—	%		—	—			38,979
33 Stiles Lane	6.75	%		3/1/2022	2,785			3,132
97 Newberry Road	5.71	%		3/1/2026	6,375			6,819
Secured fixed rate debt	5.68	%	(1)		$	247,562		$	598,660
					$	1,711,666		$	2,201,537
Unamortized net premiums and discounts					(1,342		)	6,128
					$	1,710,324		$	2,207,665

(1) Represents weighted average interest rate at December 31, 2015.

(2) Interest on this loan is payable at LIBOR plus 2.625% but has been fixed for the first seven years to December 1, 2016 by a cash flow hedge which sets 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, 2015 are as follows (in thousands):

2016	$	142,450
2017	294,865
2018	253,847
2019	164,613
2020	451,674
Thereafter	404,217
	$	1,711,666