Debt

The Company does not have indebtedness as debt is incurred by the Operating Partnership. The Company guarantees the Operating Partnership’s unsecured debt including the revolving credit facilities for the full term of the facilities.

Debt consists of the following ($ in thousands):



	September 30, 2018			December 31, 2017			Weighted Average Maturity In Years as of September 30, 2018
Unsecured bonds private placement - fixed rate	$	274,574		$	274,427		2.3
Term loan - variable rate	348,717			348,545			3.4
Bonds public offering - fixed rate	3,175,414			2,878,737			7.9
Unsecured debt, net ⁽¹⁾	3,798,705			3,501,709
Lines of credit ⁽²⁾	—			179,000
Mortgage notes payable, net ⁽³⁾	1,834,967			2,008,417			4.5
Total debt, net	$	5,633,672		$	5,689,126
Weighted average interest rate on fixed rate unsecured bonds private placement and bonds public offering	3.9		%	3.7		%
Weighted average interest rate on variable rate term loan	2.8		%	2.5		%
Weighted average interest rate on lines of credit	3.0		%	2.3		%
Weighted average interest rate on mortgage notes payable	4.4		%	4.2		%

(1) Includes unamortized discount of $7.0 million and $5.2 million and unamortized debt issuance costs of $19.3 million and $18.1 million, as of September 30, 2018 and December 31, 2017, respectively.

(2) Lines of credit, related to the Company's two lines of unsecured credit aggregating $1.24 billion as of September 30, 2018, excludes unamortized debt issuance costs of $4.2 million and $3.2 million as of September 30, 2018 and December 31, 2017, respectively. These debt issuance costs are included in prepaid expenses and other assets on the condensed consolidated balance sheets. As of September 30, 2018, the Company’s $1.2 billion credit facility had an interest rate of LIBOR plus 0.875%, which is based on a tiered rate structure tied to the Company’s credit ratings and a scheduled maturity date of December 2021 with one 18-month extension, exercisable at the Company’s option. As of September 30, 2018, the Company’s $35.0 million working capital unsecured line of credit had an interest rate of LIBOR plus 0.875%, which is based on a tiered rate structure tied to the Company’s credit ratings and a scheduled maturity date of January 2020.

(3) Includes total unamortized premium of $21.2 million and $33.2 million, reduced by unamortized debt issuance costs of $4.4 million and $5.4 million, as of September 30, 2018 and December 31, 2017, respectively.

The aggregate scheduled principal payments of the Company’s outstanding debt as of September 30, 2018 are as follows (excluding lines of credit) ($ in thousands):



Remaining in 2018	$	68,054
2019	605,688
2020	693,723
2021	543,604
2022	691,178
Thereafter	3,040,928
Total	$	5,643,175