Summary of Significant Accounting Policies Tax (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Summary Of Significant Accounting Policies [Abstract]
State and local income, franchise and excise tax (benefit)	$ 915	$ 852	$ 963
Alternative minimum tax credit (benefit)			(3,244)
Income and other tax expense (benefit)	$ 915	$ 852	$ (2,281)
Tax Treatment Of Dividends And Distributions Ordinary Dividends	$ 1.40791	$ 1.34739	$ 1.39604
Tax Treatment Of Dividends And Distributions Long Term Capital Gain	0.73687	0.77923	0.61243
Tax Treatment Of Dividends And Distributions Unrecaptured Section Twelve Hundred And Fifty Gain	0.26522	0.24838	0.23403
Dividends and distributions declared per Common Share outstanding	$ 2.41000	$ 2.37500	$ 2.24250