Debt Instrument Restructured Loan Effective Date.

No definition available.

Name:	hcn_DebtInstrumentRestructuredLoanEffectiveDate
Namespace Prefix:	hcn_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense related to estimated loss from loan and lease transactions excluding allowance for write-off.

+ References

No definition available.

+ Details

Name:	hcn_ProvisionForLoanAndLeaseLossesRealEstateExcludingWriteOff
Namespace Prefix:	hcn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488

+ Details

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=hcn_TripleNetMember
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- Details

Name:	us-gaap_LoanRestructuringModificationNameAxis=hcn_GensisHealthcareLoanMaturingIn2017MemberMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_LoanRestructuringModificationNameAxis=hcn_GensisHealthcareLoanMaturingIn2018MemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_LoanRestructuringModificationNameAxis=hcn_GenesisHealthcareFourRestructuredLoansMemberMember
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Real Estate Loans Receivable (Textuals) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Financing Receivable, Modifications [Line Items]
Allowance for loan losses	$ 6,196	$ 6,563	$ 0
Genesis Healthcare Loans [Member] \| Triple Net [Member]
Financing Receivable, Modifications [Line Items]
Long-term Debt, Gross	$ 317,000
Provision For Loan And Lease Losses Real Estate Excluding Write Off		$ 6,935
Gensis Healthcare Loan Maturing In 2017 [Member] \| Triple Net [Member]
Financing Receivable, Modifications [Line Items]
Maturity Date	Feb. 28, 2017
Gensis Healthcare Loan Maturing In 2018 [Member] \| Triple Net [Member]
Financing Receivable, Modifications [Line Items]
Maturity Date	Sep. 30, 2018
Genesis Healthcare Four Restructured Loans [Member] \| Triple Net [Member]
Financing Receivable, Modifications [Line Items]
Debt Instrument Restructured Loan Effective Date	Oct. 01, 2016
Debt Instrument, Term	5 years
Debt Instrument Interest Rate Stated Percentage	10.00%
Debt Instrument Basis Spread On Variable Rate1	0.25%