Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Intangible lease assets, accumulated amortization	$ 80,072	$ 67,850
Tenant receivables, allowance for doubtful accounts	4,965	4,553
Deferred lease costs, accumulated amortization	195,255	171,817
Liabilities:
Intangible lease liabilities, accumulated amortization	$ 33,619	$ 27,344
Stockholders’ Equity:
Shares-in-trust, shares authorized (in shares)	150,000,000	150,000,000
Shares-in-trust, shares outstanding (in shares)	0	0
Preferred stock, par value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	124,135,626	123,839,419
Common stock, shares outstanding (in shares)	124,135,626	123,839,419
Unsecured Debt
Liabilities:
Discount (premiums) and unamortized debt issuance costs	$ 12,899	$ 10,932
Secured Debt
Liabilities:
Discount (premiums) and unamortized debt issuance costs	0	(326)
Building and improvements
Assets:
Buildings and improvements, accumulated depreciation	$ 829,832	$ 751,521