CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Total Stockholders’ Equity	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Cumulative Dividends in Excess of Earnings	Noncontrolling Interests
Beginning balance at Dec. 31, 2015	$ 1,406,958	$ 1,379,424	$ 1,270	$ 2,328,806	$ 0	$ (950,652)	$ 27,534
Beginning balance (in shares) at Dec. 31, 2015			127,027,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in HTA	417,163	417,163	$ 141	417,022
Issuance of common stock in HTA (in shares)			14,138,000
Issuance of operating partnership units in HTALP in connection with an acquisition	74,460						74,460
Share-based award transactions, net	7,071	7,071	$ 4	7,067
Share-based award transactions, net (in shares)			391,000
Repurchase and cancellation of common stock	(2,642)	(2,642)	$ (1)	(2,641)
Repurchase and cancellation of common stock (in shares)			(94,000)
Redemption of noncontrolling interest and other	(1,142)	4,567	$ 3	4,564			(5,709)
Redemption of noncontrolling interest and other (in shares)			257,000
Dividends declared	(168,678)	(164,221)				(164,221)	(4,457)
Net income	47,227	45,912				45,912	1,315
Other comprehensive income (loss)	0
Ending balance at Dec. 31, 2016	1,780,417	1,687,274	$ 1,417	2,754,818	0	(1,068,961)	93,143
Ending balance (in shares) at Dec. 31, 2016			141,719,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in HTA	1,746,956	1,746,956	$ 628	1,746,328
Issuance of common stock in HTA (in shares)			62,823,000
Issuance of operating partnership units in HTALP in connection with an acquisition	1,125						1,125
Share-based award transactions, net	6,870	6,870	$ 3	6,867
Share-based award transactions, net (in shares)			230,000
Repurchase and cancellation of common stock	(3,413)	(3,413)	$ (1)	(3,412)
Repurchase and cancellation of common stock (in shares)			(116,000)
Redemption of noncontrolling interest and other	(2,014)	3,929	$ 2	3,927			(5,943)
Redemption of noncontrolling interest and other (in shares)			236,000
Dividends declared	(232,227)	(227,024)				(227,024)	(5,203)
Net income	65,454	63,916				63,916	1,538
Other comprehensive income (loss)	280	274			274		6
Ending balance at Dec. 31, 2017	$ 3,363,448	3,278,782	$ 2,049	4,508,528	274	(1,232,069)	84,666
Ending balance (in shares) at Dec. 31, 2017	204,892,118		204,892,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in HTA	$ 72,814	72,814	$ 25	72,789
Issuance of common stock in HTA (in shares)			2,550,000
Share-based award transactions, net	10,166	9,755	$ 4	9,751			411
Share-based award transactions, net (in shares)			308,000
Repurchase and cancellation of common stock	(70,319)	(70,319)	$ (27)	(70,292)
Repurchase and cancellation of common stock (in shares)			(2,678,000)
Redemption of noncontrolling interest and other	0	5,195	$ 2	5,193			(5,195)
Redemption of noncontrolling interest and other (in shares)			195,000
Dividends declared	(258,766)	(253,699)				(253,699)	(5,067)
Net income	217,537	213,463				213,463	4,074
Other comprehensive income (loss)	34	33			33		1
Ending balance at Dec. 31, 2018	$ 3,334,914	$ 3,256,024	$ 2,053	$ 4,525,969	$ 307	$ (1,272,305)	$ 78,890
Ending balance (in shares) at Dec. 31, 2018	205,267,349		205,267,000