Summary of Significant Accounting Policies (Details) - USD ($)		3 Months Ended		6 Months Ended		7 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jul. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents		$ 75,202,000	$ 23,194,000	$ 75,202,000	$ 23,194,000		$ 32,713,000
Restricted cash		4,798,000	5,950,000	4,798,000	5,950,000		4,903,000
Total cash, cash equivalents and restricted cash		80,000,000	29,144,000	$ 80,000,000	29,144,000		$ 37,616,000	$ 133,530,000
Leases [Abstract]
Deferred rent period				3 months
Amount of rent deferrals		6,600,000		$ 6,600,000
Net income attributable to noncontrolling interests	[1]	$ 236,000	339,000	$ 543,000	600,000
Unconsolidated Joint Ventures [Abstract]
Investment in unconsolidated joint ventures, ownership percentage		50.00%		50.00%			50.00%
Investment in unconsolidated joint venture		$ 65,120,000		$ 65,120,000			$ 65,888,000
Income (loss) from unconsolidated joint venture		$ 379,000	548,000	801,000	1,034,000
Subsequent Event
Leases [Abstract]
Amount of rent deferrals						$ 9,600,000
Secured Debt
Leases [Abstract]
Debt term		1 year
Debt instrument, face amount		$ 6,000,000		$ 6,000,000
Minimum
Leases [Abstract]
Lessor, term of contract		3 years		3 years
Deferred rent payback period				12 months
Maximum
Leases [Abstract]
Lessor, term of contract		7 years		7 years
Deferred rent payback period				3 months
Building and Building Improvements
Real estate investments [Abstract]
Depreciation expense		$ 58,200,000	51,900,000	$ 117,100,000	104,000,000.0
Healthcare Trust of America Holdings, LP (HTALP)
Partners' Capital Notes [Abstract]
Limited partner's capital, units issued (in shares)		3,568,369		3,568,369			3,834,279
Limited partner's capital, units outstanding (in shares)		3,568,369		3,568,369			3,834,279
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents		$ 75,202,000		$ 75,202,000			$ 32,713,000
Restricted cash		4,798,000		4,798,000			4,903,000
Total cash, cash equivalents and restricted cash		80,000,000	29,144,000	80,000,000	29,144,000		37,616,000	$ 133,530,000
Leases [Abstract]
Net income attributable to noncontrolling interests		0	38,000	0	66,000
Unconsolidated Joint Ventures [Abstract]
Investment in unconsolidated joint venture		65,120,000		65,120,000			$ 65,888,000
Income (loss) from unconsolidated joint venture		$ 379,000	$ 548,000	$ 801,000	$ 1,034,000

[1] Includes amounts attributable to redeemable noncontrolling interests for the three and six months ended June 30, 2019.