Line of Credit Facility, Extension Option, Period

No definition available.

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- Definition

Line of Credit Facility, Number of Extension Options

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

[Line Items] for Mortgages Payable [Table]

+ References

No definition available.

+ Details

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

- Definition

Number of Tranches

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of short-term and long-term debt and lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
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-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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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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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
-Paragraph 2
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+ Details

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

- 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

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

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

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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+ Details

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

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

+ References

No definition available.

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
-Paragraph 14
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+ Details

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

- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

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+ Details

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

- Definition

Amount of cash outflow for the payment of debt classified as other, maturing after one year or the operating cycle, if longer.

+ References

+ Details

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

- Details

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- Details

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- Details

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- Details

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- Details

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Period Type:

- Details

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Debt - Narrative (Details)		3 Months Ended	12 Months Ended
Debt - Narrative (Details)	Dec. 21, 2018 USD ($) derivative_instrument	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Mortgages Payable [Line Items]
Debt, net		$ 555,109,000	$ 555,109,000	$ 572,850,000
Repayment of mortgages payable			67,349,000
Revolving Credit Facility, Amended and Restated
Mortgages Payable [Line Items]
Repaid amount		100,000,000
Mortgages
Mortgages Payable [Line Items]
Long-term debt, net		$ 106,728,000	$ 106,728,000	$ 175,321,000
Weighted average interest rate (percent)		4.07%	4.07%	4.34%
Mortgages \| Minimum
Mortgages Payable [Line Items]
Stated interest rate		3.49%	3.49%	3.49%
Mortgages \| Maximum
Mortgages Payable [Line Items]
Stated interest rate		4.58%	4.58%	5.49%
Revolving line of credit \| Revolving Credit Facility, Amended and Restated
Mortgages Payable [Line Items]
Debt, net		$ 50,000,000	$ 50,000,000
Maximum borrowing capacity	$ 350,000,000	50,000,000	50,000,000	$ 50,000,000
Proceeds from lines of credit			$ 150,000,000
Debt instrument, term	4 years
Number of extension options \| derivative_instrument	2
Extension option	6 months
Interest rate (percentage)			1.19%	1.19%
Long-term line of credit		0	$ 0	$ 0
Outstanding borrowings		300,000,000	$ 300,000,000
Leverage ratio, fee percentage			0.15%
Revolving line of credit \| Revolving Credit Facility, Amended and Restated \| Carrying Value
Mortgages Payable [Line Items]
Line of credit and term loan, estimated fair value		50,000,000	$ 50,000,000	0
Revolving line of credit \| Revolving Credit Facility, Amended and Restated \| London Interbank Offered Rate (LIBOR)
Mortgages Payable [Line Items]
Basis spread on variable rate (percent)			1.05%
Unsecured Debt \| Term Loan
Mortgages Payable [Line Items]
Long-term debt, net		398,381,000	$ 398,381,000	397,529,000
Debt instrument, face amount	$ 400,000,000
Number of tranches \| derivative_instrument	2
Unsecured Debt \| Term Loan \| Carrying Value
Mortgages Payable [Line Items]
Line of credit and term loan, estimated fair value		$ 400,000,000	$ 400,000,000	$ 400,000,000
Unsecured Debt \| Term Loan, Tranche One
Mortgages Payable [Line Items]
Debt instrument, term	5 years
Debt instrument, face amount	$ 250,000,000
Unsecured Debt \| Term Loan, Tranche Two
Mortgages Payable [Line Items]
Debt instrument, term	5 years 6 months
Debt instrument, face amount	$ 150,000,000