Stockholders' Equity and Partners' Capital - Textuals (Details)		1 Months Ended		3 Months Ended			9 Months Ended
	Oct. 27, 2015 $ / shares	May. 31, 2015 $ / shares shares	Feb. 28, 2014 USD ($)	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($) $ / shares		Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($) $ / shares
Common Stock Dividends
Dividends declared (in usd per share)				$ 0.30	$ 0.29	[1]	$ 0.88	$ 0.87	[1]
LTIP Units
Incentive Plan
Number of forfeited units/shares | shares		225,000
Weighted average grant date fair value of units forfeited (in usd per share)		$ 20.00
Restricted Common Stock
Incentive Plan
Number of forfeited units/shares | shares							21,378
Weighted average grant date fair value of units forfeited (in usd per share)							$ 22.70
Allocated share-based compensation expense | $				$ 1,400,000	$ 1,000,000		$ 4,500,000	$ 3,300,000
Nonvested awards, total compensation cost not yet recognized | $				$ 5,300,000			$ 5,300,000
Period for recognition							1 year 4 months 24 days
2006 Incentive Plan
Incentive Plan
Number of shares authorized | shares				5,000,000			5,000,000
Number of shares available for grant | shares				2,316,162			2,316,162
Subsequent Event
Common Stock Dividends
Dividends declared (in usd per share)	$ 0.295
At the Market
Common Stock Offerings
Number of shares issued and sold | shares							1,800,000
Sale of stock, average price per share (in usd per share)							$ 25.00
Remaining available amount of common stock for issuance | $							$ 211,600,000
At the Market | Maximum
Common Stock Offerings
Maximum amount of common stock authorized | $			$ 300,000,000
Healthcare Trust of America Holdings, LP (HTALP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend distribution ratio							1
Common Stock Dividends
Dividends declared (in usd per share)				$ 0.30	$ 0.29	[1]	$ 0.88	$ 0.87	[1]

[1] For the three and nine months ended September 30, 2014, amounts have been adjusted retroactively to reflect a 1-for-2 reverse stock split effected on December 15, 2014.