Debt

Debt consisted of the following as of September 30, 2013 and December 31, 2012 (in thousands):



	September 30, 2013		December 31, 2012
Unsecured revolving credit facility	$	—	$	72,000
Unsecured term loans	455,000		455,000
Unsecured senior notes	300,000		—
Fixed rate mortgages	370,636		382,456
Secured real estate term loan	—		125,500
	1,125,636		1,034,956
Net premium	156		2,403
Total	$	1,125,792	$	1,037,359

Unsecured Credit Agreement

On March 29, 2012, we entered into an unsecured credit agreement to obtain a $575.0 million unsecured revolving credit facility and a $300.0 million unsecured term loan. On March 7, 2013, we executed an amendment to the unsecured credit agreement pursuant to an existing provision therein to increase the principal amount of the unsecured revolving credit facility. This amendment added an additional lender and increased the unsecured revolving credit facility by $75.0 million to $650.0 million. The other existing terms of the unsecured credit agreement were unchanged. The unsecured credit agreement matures on March 29, 2016 and includes a one-year extension option, subject to certain conditions.

The actual amount of credit available under our unsecured credit agreement is a function of certain loan-to-value and debt service coverage ratios. The maximum principal amount may be increased; subject to such additional financing being provided by our existing lenders or new lenders added to the unsecured revolving credit facility.

Borrowings under the $650.0 million unsecured revolving credit facility accrue interest equal to adjusted LIBOR plus a margin ranging from 1.10% to 1.75% per annum based on our credit rating. We also pay a facility fee ranging from 0.20% to 0.50% per annum on the aggregate commitments under the unsecured revolving credit facility. As of September 30, 2013, the margin associated with borrowings was 1.55% per annum and the facility fee was 0.35% per annum. As of September 30, 2013, no amount was outstanding on our unsecured revolving credit facility.

Borrowings under the $300.0 million unsecured term loan accrue interest equal to adjusted LIBOR plus a margin ranging from 1.30% to 2.25% per annum based on our credit rating. The margin associated with borrowings as of September 30, 2013 was 1.85% per annum. We have interest rate swaps in place that fix the interest rate at 2.95% per annum, based on our current credit rating.

$155.0 million Unsecured Term Loan

On July 20, 2012, we entered into a $155.0 million unsecured term loan that matures on July 19, 2019. The interest rate thereon is equal to LIBOR plus a margin ranging from 1.55% to 2.40% per annum based on our credit rating. The margin associated with the borrowings as of September 30, 2013 was 2.00% per annum. We have interest rate swaps in place that fix the interest rate at 3.29% per annum, based on our current credit rating. The maximum principal amount may be increased by us, subject to such additional financing being provided by our existing lender.

$300.0 million Unsecured Senior Notes

On March 28, 2013, we issued $300.0 million of unsecured senior notes that mature on April 15, 2023. The unsecured senior notes bear interest at 3.70% per annum payable semi-annually and were offered at 99.186% of the principal amount thereof. The unsecured senior notes include registration rights to the holders, pursuant to which we filed an exchange offer on Form S-4 on October 22, 2013.

Fixed Rate Mortgages

As of September 30, 2013, we had fixed rate mortgages with interest rates ranging from 4.55% to 12.75% per annum and a weighted average interest rate of 5.86% per annum. As part of an acquisition, we assumed two mortgage loans; see Note 3, Business Combinations.

Secured Real Estate Term Loan

On March 28, 2013, we repaid in full the $125.5 million secured real estate term loan. In connection with that repayment, we terminated the secured real estate term loan (and the commitments thereunder) and the related security documents and guarantees. In addition, we terminated the $75.0 million interest rate swap associated with the secured real estate term loan.

Future Debt Maturities

As of September 30, 2013, the principal payments due on our debt for the three months ending December 31, 2013, for each of the next four years ending December 31 and thereafter, is as follows (in thousands):



Year	Amount
2013	$	1,722
2014	6,872
2015	73,128
2016	421,578
2017	99,963
Thereafter	522,373
Total	$	1,125,636

The above scheduled debt maturities do not include the available extension under the unsecured credit agreement as discussed above.

We are required by the terms of our applicable credit agreements to meet various affirmative and negative covenants that we believe are customary for these types of facilities, such as limitations on the incurrence of debt by us, and our subsidiaries that own unencumbered assets, limitations on the nature of HTALP’s business, and limitations on distributions by HTALP and its subsidiaries that own unencumbered assets. Our credit agreements also impose various financial covenants on us, such as a maximum ratio of total indebtedness to total asset value, a minimum ratio of EBITDA to fixed charges, a minimum tangible net worth covenant, a maximum ratio of unsecured indebtedness to unencumbered asset value, rent coverage ratios, and a minimum ratio of unencumbered net operating income to unsecured interest expense. As of September 30, 2013, we believe that we were in compliance with all such financial covenants and reporting requirements. In addition, certain of our credit agreements include events of default provisions that we believe are customary for these types of facilities, including restricting HTA from making dividend distributions to our stockholders in the event we are in default, except to the extent necessary for HTA to maintain its REIT status.