Debt Instrument, Number Of Loans

No definition available.

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Period Type:	instant

- Definition

Weighted average interest rate on debt during the period.

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility Required Principal Payment Before Maturity

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of buildings serving as collateral for debt as of the balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Represents the number of communities.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The number of real estate properties owned by the entity, which are classified as held for sale as of the balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Real Estate Investment Property, Lease Obligations

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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+ Details

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

- Definition

Increase for accrued, but unpaid interest on the debt instrument for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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

- Definition

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

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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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Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The aggregate amount of the participating mortgage obligation at the end of the accounting period.

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
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- Details

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- Details

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- Details

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- Details

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Indebtedness (Details)		1 Months Ended			3 Months Ended
Indebtedness (Details)	Apr. 01, 2020	May 31, 2020 USD ($) property	Apr. 30, 2020 USD ($)	Feb. 29, 2020 property	Mar. 31, 2020 USD ($) building loan property	Mar. 31, 2019 USD ($)	May 06, 2020 USD ($)	Dec. 31, 2019 USD ($)
Indebtedness
Total real estate properties, gross					$ 7,434,672,000			$ 7,461,586,000
Unsecured revolving credit facility					585,000,000			537,500,000
Loss on early extinguishment of debt					$ 246,000	$ 0
Joint Venture
Indebtedness
Ownership percentage					55.00%
Unsecured revolving credit facility
Indebtedness
Unsecured revolving credit facility, maximum borrowing capacity					$ 1,000,000,000
Revolving credit facility, interest rate payable (as a percent)					1.80%
Weighted average interest rate on debt (as a percent)					2.60%	3.60%
Line of credit facility, periodic payment, principal					$ 0
Unsecured revolving credit facility					585,000,000
Revolving credit facility, available amount					$ 415,000,000
Unsecured revolving credit facility \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)					1.20%
Debt instrument, facility fee (as a percent)					0.25%
Unsecured revolving credit facility \| Subsequent Event
Indebtedness
Unsecured revolving credit facility							$ 775,000,000
Revolving credit facility, available amount							$ 225,000,000
Unsecured revolving credit facility \| Subsequent Event \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)	1.55%
Debt instrument, facility fee (as a percent)	0.30%
Mortgages
Indebtedness
Aggregate principal amount of mortgage debt					$ 687,154,000
Number of buildings mortgaged \| building					8
Total real estate properties, gross					$ 1,271,352,000
Principal mortgage obligations					$ 1,267,000
Number of real estate properties held for sale \| building					1
Mortgages \| Joint Venture
Indebtedness
Aggregate principal amount of mortgage debt					$ 620,000,000
Ownership percentage					55.00%
Capital leases
Indebtedness
Number of buildings mortgaged \| property					2
Total real estate properties, gross					$ 35,627,000
Lease obligations					$ 8,615,000
Term loan due 2020
Indebtedness
Debt face amount								$ 250,000,000
Weighted average interest rate on debt (as a percent)					2.70%
Interest rate (as a percent)								1.90%
Term loan due 2020 \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)					1.25%
Term loan due 2020 \| Subsequent Event \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)	1.65%
Term loan due 2022
Indebtedness
Debt face amount					$ 200,000,000
Weighted average interest rate on debt (as a percent)					3.10%	3.90%
Interest rate (as a percent)					2.30%
Term loan due 2022 \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)					1.35%
Term loan due 2022 \| Subsequent Event \| LIBOR
Indebtedness
Interest rate added to the base rate (as a percent)	1.75%
Senior Unsecured Note Due March 2026 \| Life Science Building
Indebtedness
Debt face amount					$ 1,554,000
Interest rate (as a percent)					6.25%
Number of communities \| property				1
Loss on early extinguishment of debt					$ 246,000
Senior Unsecured Note Due 2020 \| Subsequent Event
Indebtedness
Interest rate (as a percent)			6.75%
Principal amount plus accrued and unpaid interest			$ 200,000,000
Unpaid interest			$ 6,750,000
Mortgage 7.49 Percent Due January 2022 \| Subsequent Event \| Medical Office Buildings
Indebtedness
Debt face amount		$ 1,213,000
Interest rate (as a percent)		7.49%
Number of communities \| property		1
Unsecured Debt
Indebtedness
Debt face amount					1,850,000,000
Term Loan
Indebtedness
Debt face amount					$ 450,000,000
Number of loans \| loan					2