Reportable Segments - Segment Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total Revenues	$ 802,874	$ 762,290	$ 755,073
Rental property revenues
Segment Reporting Information [Line Items]
Total Revenues	799,047	753,511	739,063
Rental property revenues | Office
Segment Reporting Information [Line Items]
Total Revenues	791,905	748,477	736,365
Rental property revenues | Non-Office
Segment Reporting Information [Line Items]
Total Revenues	7,142	5,034	2,698
Rental property revenues | Operating Segments
Segment Reporting Information [Line Items]
Total Revenues	808,008	768,448	767,856
Rental property revenues | Operating Segments | Atlanta
Segment Reporting Information [Line Items]
Total Revenues	298,185	280,209	270,412
Rental property revenues | Operating Segments | Austin
Segment Reporting Information [Line Items]
Total Revenues	262,425	249,776	247,806
Rental property revenues | Operating Segments | Charlotte
Segment Reporting Information [Line Items]
Total Revenues	65,485	60,346	77,402
Rental property revenues | Operating Segments | Dallas
Segment Reporting Information [Line Items]
Total Revenues	16,948	16,736	17,670
Rental property revenues | Operating Segments | Phoenix
Segment Reporting Information [Line Items]
Total Revenues	64,073	57,635	59,614
Rental property revenues | Operating Segments | Tampa
Segment Reporting Information [Line Items]
Total Revenues	74,813	70,984	50,292
Rental property revenues | Operating Segments | Other markets
Segment Reporting Information [Line Items]
Total Revenues	26,079	32,762	44,660
Rental property revenues | Operating Segments | Office
Segment Reporting Information [Line Items]
Total Revenues	798,987	757,692	758,440
Rental property revenues | Operating Segments | Office | Atlanta
Segment Reporting Information [Line Items]
Total Revenues	296,306	278,418	268,953
Rental property revenues | Operating Segments | Office | Austin
Segment Reporting Information [Line Items]
Total Revenues	262,425	249,776	247,806
Rental property revenues | Operating Segments | Office | Charlotte
Segment Reporting Information [Line Items]
Total Revenues	58,343	55,312	74,702
Rental property revenues | Operating Segments | Office | Dallas
Segment Reporting Information [Line Items]
Total Revenues	16,948	16,736	17,670
Rental property revenues | Operating Segments | Office | Phoenix
Segment Reporting Information [Line Items]
Total Revenues	64,073	57,635	50,292
Rental property revenues | Operating Segments | Office | Tampa
Segment Reporting Information [Line Items]
Total Revenues	74,813	70,984	59,614
Rental property revenues | Operating Segments | Office | Other markets
Segment Reporting Information [Line Items]
Total Revenues	26,079	28,831	39,403
Rental property revenues | Operating Segments | Non-Office
Segment Reporting Information [Line Items]
Total Revenues	9,021	10,756	9,416
Rental property revenues | Operating Segments | Non-Office | Atlanta
Segment Reporting Information [Line Items]
Total Revenues	1,879	1,791	1,459
Rental property revenues | Operating Segments | Non-Office | Austin
Segment Reporting Information [Line Items]
Total Revenues	0	0	0
Rental property revenues | Operating Segments | Non-Office | Charlotte
Segment Reporting Information [Line Items]
Total Revenues	7,142	5,034	2,700
Rental property revenues | Operating Segments | Non-Office | Dallas
Segment Reporting Information [Line Items]
Total Revenues	0	0	0
Rental property revenues | Operating Segments | Non-Office | Phoenix
Segment Reporting Information [Line Items]
Total Revenues	0	0	0
Rental property revenues | Operating Segments | Non-Office | Tampa
Segment Reporting Information [Line Items]
Total Revenues	0	0	0
Rental property revenues | Operating Segments | Non-Office | Other markets
Segment Reporting Information [Line Items]
Total Revenues	0	3,931	5,257
Rental property revenues | Segment Reconciling Items
Segment Reporting Information [Line Items]
Total Revenues	(8,961)	(14,937)	(28,793)
Rental property revenues | Segment Reconciling Items | Office
Segment Reporting Information [Line Items]
Total Revenues	(7,082)	(9,215)	(22,075)
Rental property revenues | Segment Reconciling Items | Non-Office
Segment Reporting Information [Line Items]
Total Revenues	$ (1,879)	$ (5,722)	$ (6,718)