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Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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Fair value of the amount outstanding under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Transactions with Affiliates - Narrative (Details) - USD ($)		1 Months Ended		12 Months Ended
	Jun. 30, 2018	Jul. 31, 2018	May 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Management fee, percent of net asset value				1.25%
Management fee, amount				$ 1,000,000
Proceeds from sale of equity method investments				142,270,000	$ 0	$ 0
Gain on sale of real estate				167,231,000	137,370,000	73,616,000
Due to affiliates—contingent consideration for Internalization				0	23,534,000
Contingent consideration
Related Party Transaction [Line Items]
Due to affiliates—contingent consideration for Internalization					20,650,000
American Healthcare Investors, LLC \| Management and Advisory Fees
Related Party Transaction [Line Items]
Property management and sub-advisory fees				$ 4,100,000	4,800,000
Minimum \| Healthcare Strategic Partnership
Related Party Transaction [Line Items]
Incentive fee percentage				20.00%
Maximum \| Healthcare Strategic Partnership
Related Party Transaction [Line Items]
Incentive fee percentage				25.00%
NorthStar Healthcare \| Revolving Credit Facility \| Line of Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Maximum principal amount of credit facility				$ 35,000,000.0
Extension option, term				6 months
Outstanding advances				$ 0	0
Colony Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Proceeds from sale of equity method investments			$ 89,100,000
Proceeds from sale of real estate		$ 121,500,000
Gain on sale of real estate		$ 28,600,000
LIBOR \| NorthStar Healthcare \| Revolving Credit Facility \| Line of Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Basis spread on variable rate, percent				3.50%
Redeemable noncontrolling interests \| Investment Vehicles \| Affiliated Entity
Related Party Transaction [Line Items]
Investments				$ 5,700,000	4,800,000
Net income attributable to noncontrolling interest				400,000
Senior Management \| Contingent consideration
Related Party Transaction [Line Items]
Due to affiliates—contingent consideration for Internalization				0	20,650,000
Common Stock And OP Units \| Senior Management \| Affiliated Entity \| Contingent consideration
Related Party Transaction [Line Items]
Transfer out of liabilities into equity	$ 12,500,000
Cost reimbursements \| Corporate Aircraft Use Reimbursement
Related Party Transaction [Line Items]
Revenue from contract with customer				700,000	1,900,000	900,000
Cost reimbursements \| Affiliated Entity
Related Party Transaction [Line Items]
Revenue from contract with customer				34,695,000	$ 25,630,000	$ 4,296,000
Contingent consideration \| Level 3 \| Recurring
Related Party Transaction [Line Items]
Transfer out of liabilities into equity				12,539,000
Transfers out of Level 3				$ 6,381,000
Contingent consideration \| Level 3 \| Recurring \| Senior Management \| Contingent consideration
Related Party Transaction [Line Items]
Transfers out of Level 3	$ 6,400,000