CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Rental income:
Total rental income	$ 1,448,120	$ 1,494,892	$ 1,609,876
Income from loans and investments	74,981	80,505	89,201
Interest and other income	14,809	7,609	10,984
Total revenues	3,828,007	3,795,357	3,872,750
Expenses
Interest	440,089	469,541	451,662
Depreciation and amortization	1,197,403	1,109,763	1,045,620
Property-level operating expenses:
Property-level operating expenses	2,084,064	1,937,443	1,808,208
Office building and other services costs	4,433	2,315	2,319
General, administrative and professional fees	129,758	130,158	158,726
Loss on extinguishment of debt, net	59,299	10,791	41,900
Transaction expenses and deal costs	47,318	29,812	15,235
Allowance on loans receivable and investments	(9,082)	24,238	0
Other	37,110	707	(10,339)
Total expenses	3,990,392	3,714,768	3,513,331
(Loss) income before unconsolidated entities, real estate dispositions, income taxes and noncontrolling interests	(162,385)	80,589	359,419
Income (loss) from unconsolidated entities	4,983	1,844	(2,454)
Gain on real estate dispositions	218,788	262,218	26,022
Income tax (expense) benefit	(4,827)	96,534	56,310
Income from continuing operations	56,559	441,185	439,297
Net income	56,559	441,185	439,297
Net income attributable to noncontrolling interests	7,551	2,036	6,281
Net income attributable to common stockholders	$ 49,008	$ 439,149	$ 433,016
Basic:
Income from continuing operations (USD per share)	$ 0.15	$ 1.18	$ 1.20
Net income attributable to common stockholders (USD per share)	0.13	1.18	1.18
Diluted:
Income from continuing operations (USD per share)	0.15	1.17	1.19
Net income attributable to common stockholders (USD per share)	$ 0.13	$ 1.17	$ 1.17
Retained Earnings (Deficit)
Property-level operating expenses:
Net income	$ 49,008	$ 439,149	$ 433,016
Net income attributable to common stockholders	49,008
Triple-net leased properties
Rental income:
Total rental income	653,823	695,265	780,898
Property-level operating expenses:
Property-level operating expenses	15,335	22,160	26,561
Office operations
Rental income:
Total rental income	794,297	799,627	828,978
Property-level operating expenses:
Property-level operating expenses	257,001	256,612	260,249
Resident fees and services
Rental income:
Revenue from contracts with customers	2,270,001	2,197,160	2,151,533
Office building and other services revenue
Rental income:
Revenue from contracts with customers	20,096	15,191	11,156
Senior living operations
Property-level operating expenses:
Property-level operating expenses	$ 1,811,728	$ 1,658,671	$ 1,521,398