Fair Value of Assets and Liabilities (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Schedule of assets measured on a recurring and non-recurring basis at fair value, categorized by the level of inputs used in the valuation assets

The table below presents certain of our assets measured at fair value at September 30, 2018, categorized by the level of inputs, as defined in the fair value hierarchy under GAAP, used in the valuation of each asset:

			Fair Value at Reporting Date Using
			Quoted Prices in				Significant
			Active Markets for		Significant Other		Unobservable
			Identical Assets		Observable Inputs		Inputs
Description	Total		(Level 1)		(Level 2)		(Level 3)
Recurring Fair Value Measurements Assets:
Investment in RMR Inc. (1)	$	112,680	$	112,680	$	—	$	—

(1) Our 1,214,225 shares of class A common stock of The RMR Group Inc., or RMR Inc., which are included in other assets in our condensed consolidated balance sheets, are reported at fair value which is based on quoted market prices (Level 1 inputs as defined in the fair value hierarchy under GAAP). Our historical cost basis for these shares is $26,888 as of September 30, 2018. During the three and nine months ended September 30, 2018, we recorded an unrealized gain of $17,425 and $40,677, respectively, to adjust our investment in RMR Inc. to its fair value.

Schedule of fair value and carrying value of financial instruments

At September 30, 2018 and December 31, 2017, the fair values of our financial instruments approximated their carrying values in our condensed consolidated financial statements due to their short term nature or variable interest rates, except as follows:

	As of September 30, 2018				As of December 31, 2017
	Carrying  Amount (1)		Fair Value		Carrying  Amount (1)		Fair Value
Senior unsecured notes, 3.75% interest rate, due in 2019	$	348,953	$	351,468	$	348,096	$	354,993
Senior unsecured notes, 5.875% interest rate, due in 2046	300,490		309,380		300,232		320,416
Senior unsecured notes, 4.000% interest rate, due in 2022	296,505		296,609		295,812		302,655
Mortgage note payable, 4.050% interest rate, due in 2030 (2)	64,441		62,363		64,293		65,198
Mortgage note payable, 5.720% interest rate, due in 2020 (2)	35,067		34,877		36,085		36,332
Mortgage note payable, 4.220% interest rate, due in 2022 (2)	27,408		27,422		27,906		28,432
Mortgage note payable, 4.800% interest rate, due in 2023 (2)	25,145		25,220		25,501		25,904
Mortgage note payable, 5.877% interest rate, due in 2021 (2)	13,445		13,978		13,620		14,565
Mortgage note payable, 7.000% interest rate, due in 2019 (2)	8,087		8,129		8,391		8,555
Mortgage note payable, 8.150% interest rate, due in 2021 (2)	3,235		3,360		4,111		4,340
Mortgage note payable, 4.260% interest rate, due in 2020 (2) (3)	3,047		3,028		3,193		3,216
	$	1,125,823	$	1,135,834	$	1,127,240	$	1,164,606

(1) Carrying amount includes certain unamortized debt issuance costs and unamortized premiums and discounts.

(2) We assumed these mortgages in connection with our acquisitions of the encumbered properties.  The stated interest rates for these mortgage debts are the contractually stated rates.  We recorded the assumed mortgages at estimated fair value on the date of acquisition and we are amortizing the fair value premiums, if any, to interest expense over the respective terms of the mortgages to reduce interest expense to the estimated market interest rates as of the date of acquisition.

(3) Secured by one property (one building) that is held for sale at September 30, 2018.