SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION - Reconciliation of Carrying Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Initial Cost to Company
Land	$ 44,060
Buildings and Improvements	272,927
Costs Capitalized Subsequent to Acquisition, Net	105,154
Impairment/Write Downs	(14,018)
Cost Amount Carried at Close of Period
Land	44,060
Buildings and Improvements	364,063
Total	408,123
Accumulated Depreciation	169,530	$ 156,439	$ 143,319	$ 202,700
1225 Seventeenth Street
Initial Cost to Company
Land	22,400
Buildings and Improvements	110,090
Costs Capitalized Subsequent to Acquisition, Net	46,971
Impairment/Write Downs	(3,547)
Cost Amount Carried at Close of Period
Land	22,400
Buildings and Improvements	153,514
Total	175,914
Accumulated Depreciation	59,713
1250 H Street, NW
Initial Cost to Company
Land	5,975
Buildings and Improvements	53,778
Costs Capitalized Subsequent to Acquisition, Net	21,490
Impairment/Write Downs	(4,683)
Cost Amount Carried at Close of Period
Land	5,975
Buildings and Improvements	70,585
Total	76,560
Accumulated Depreciation	40,372
206 East 9th Street
Initial Cost to Company
Land	7,900
Buildings and Improvements	38,533
Costs Capitalized Subsequent to Acquisition, Net	7,743
Impairment/Write Downs	(1,710)
Cost Amount Carried at Close of Period
Land	7,900
Buildings and Improvements	44,566
Total	52,466
Accumulated Depreciation	12,338
Bridgepoint Square
Initial Cost to Company
Land	7,785
Buildings and Improvements	70,526
Costs Capitalized Subsequent to Acquisition, Net	28,950
Impairment/Write Downs	(4,078)
Cost Amount Carried at Close of Period
Land	7,785
Buildings and Improvements	95,398
Total	103,183
Accumulated Depreciation	$ 57,107