Real Estate Loans Receivable - Credit Loss Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	$ 68,372	$ 68,372
Adoption of ASU 2016-13		0
Provision for loan losses	7,072	18,690
Foreign currency translation	(85)	0
Balance end of year	$ 80,571	$ 87,062

Amount of foreign currency translation gain (loss) which (increases) decreases allowance for credit loss on financing receivable.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Financing Receivable, Allowance For Credit Loss, Adoption

+ References

No definition available.

+ Details

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Namespace Prefix:	well_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration