6. Indebtedness

The following table discloses certain information regarding our indebtedness:



	Outstanding Balance at						Interest Rate at June 30, 2013		Effective Interest Rate at Issuance		Maturity Date
	June 30, 2013			December 31, 2012			Interest Rate at June 30, 2013		Effective Interest Rate at Issuance		Maturity Date
Mortgage Loans Payable, Net	$	631,880		$	656,329		4.03% – 8.26%		4.03% – 8.26%		January 2014- September 2022
Unamortized Premiums	(141		)	(161		)
Mortgage Loans Payable, Gross	$	631,739		$	656,168
Senior Unsecured Notes, Net
2016 Notes	$	159,538		$	159,510		5.750	%	5.91	%	1/15/2016
2017 Notes	55,388			55,385			7.500	%	7.52	%	12/1/2017
2027 Notes	6,066			6,066			7.150	%	7.11	%	5/15/2027
2028 Notes	32,257			55,261			7.600	%	8.13	%	7/15/2028
2032 Notes	10,511			11,500			7.750	%	7.87	%	4/15/2032
2014 Notes	80,401			79,683			6.420	%	6.54	%	6/1/2014
2017 II Notes	101,764			106,745			5.950	%	6.37	%	5/15/2017
Subtotal	$	445,925		$	474,150
Unamortized Discounts	1,776			2,570
Senior Unsecured Notes, Gross	$	447,701		$	476,720
Unsecured Credit Facility	$	108,000		$	98,000		1.893	%	1.893	%	12/12/2014

Mortgage Loans Payable, Net

During the three and six months ended June 30, 2013, we paid off and retired prior to maturity mortgage loans payable in the amount of $4,100 and $18,383, respectively. In connection with these prepayments, we recognized $118 and $489 as loss from retirement of debt for the three and six months ended June 30, 2013, respectively.

As of June 30, 2013, mortgage loans payable are collateralized, and in some instances cross-collateralized, by industrial properties with a net carrying value of $803,327. We believe the Operating Partnership and the Company were in compliance with all covenants relating to mortgage loans payable as of June 30, 2013.

Senior Unsecured Notes, Net

During the six months ended June 30, 2013, we repurchased and retired the following senior unsecured notes prior to maturity:



	Principal Amount Repurchased		Purchase Price
2017 II Notes	$	5,000	$	5,300
2028 Notes	23,019		26,125
2032 Notes	1,000		1,163
	$	29,019	$	32,588

In connection with these repurchases prior to maturity, we recognized $4,883 as loss from retirement of debt for the six months ended June 30, 2013, which is the difference between the repurchase price of $32,588 and the principal amount retired of $29,019, net of the pro rata write off of the unamortized debt issue discount, the unamortized deferred financing costs and the unamortized settlement amount of the interest rate protection agreements related to the repurchase of $27, $188 and $1,099, respectively.

Indebtedness

The following is a schedule of the stated maturities and scheduled principal payments as of June 30, 2013 of our indebtedness, exclusive of premiums and discounts, for the next five years ending December 31, and thereafter:



	Amount
Remainder of 2013	$	6,157
2014	241,771
2015	35,264
2016	288,953
2017	167,213
Thereafter	448,082
Total	$	1,187,440

Our unsecured credit facility (the “Unsecured Credit Facility”) and the indentures governing our senior unsecured notes contain certain financial covenants, including limitations on incurrence of debt and debt service coverage. Under the Unsecured Credit Facility, an event of default can occur if the lenders, in their good faith judgment, determine that a material adverse change has occurred which could prevent timely repayment or materially impair our ability to perform our obligations under the loan agreement. We believe that we were in compliance with all covenants as of June 30, 2013. However, these financial covenants are complex and there can be no assurance that these provisions would not be interpreted by our noteholders or lenders in a manner that could impose and cause us to incur material costs.

Fair Value

At June 30, 2013 and December 31, 2012, the fair values of our indebtedness were as follows:



	June 30, 2013				December 31, 2012
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Mortgage Loans Payable, Net	$	631,880	$	648,411	$	656,329	$	699,903
Senior Unsecured Notes, Net	445,925		481,764		474,150		516,943
Unsecured Credit Facility	108,000		108,400		98,000		98,192
Total	$	1,185,805	$	1,238,575	$	1,228,479	$	1,315,038

The fair values of our mortgage loans payable were determined by discounting the future cash flows using the current rates at which similar loans would be made based upon similar leverage levels and similar remaining maturities. The current market rates we utilized were internally estimated. The fair value of the senior unsecured notes was determined by using rates, as advised by our bankers in certain cases, that are based upon recent trades within the same series of the senior unsecured notes, recent trades for senior unsecured notes with comparable maturities, recent trades for fixed rate unsecured debt from companies with profiles similar to ours, as well as overall economic conditions. The fair value of the Unsecured Credit Facility was determined by discounting the future cash flows using current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining term, assuming no repayment until maturity. We have concluded that our determination of fair value for our mortgage loans payable, senior unsecured notes and Unsecured Credit Facility was primarily based upon Level 3 inputs.