Fair Value of Assets and Liabilities

3 Months Ended

Mar. 31, 2019

As of March 31, 2019, we do not have any assets measured at fair value.

Financial Instruments

Our financial instruments include our cash and cash equivalents, restricted cash, marketable securities, senior unsecured debt and mortgage note payable. At March 31, 2019 and December 31, 2018, the fair value of these additional financial instruments were not materially different from their carrying values, except as follows (in thousands):



	March 31, 2019				December 31, 2018
	Principal Balance		Fair Value		Principal Balance		Fair Value
Senior unsecured debt and mortgage note payable	$	275,856	$	282,710	$	276,000	$	283,214

The fair values of our senior notes are based on quoted market prices (level 2 inputs), and the fair value of our mortgage note payable is based on estimates using discounted cash flow analyses and currently prevailing interest rates adjusted by credit risk spreads (level 3 inputs).

Other financial instruments that potentially subject us to concentrations of credit risk consist principally of rents receivable; however, as of March 31, 2019, no single tenant of ours is responsible for more than 10.0% of our total annualized rents, other than one tenant that is responsible for 18.2% of our total annualized rents.