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

- Definition

Number of Tranches

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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

- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

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

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

- 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

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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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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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Balance Type:	na
Period Type:	duration

- 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
-Paragraph 4
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+ Details

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Balance Type:	credit
Period Type:	instant

- 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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Debt - Narrative (Details)		3 Months Ended	12 Months Ended
Debt - Narrative (Details)	Dec. 21, 2018 USD ($) option tranche	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Debt, net		$ 561,412,000	$ 561,782,000
Mortgages payable
Debt Instrument [Line Items]
Mortgages payable, net		$ 212,432,000	$ 212,927,000
Revolving Credit Facility \| Revolving Credit Facility, Amended and Restated
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 350,000
Debt instrument, term	4 years
Number of extension options \| option	2
Extension option on line of credit, period	6 months
Commitment fee		0.15%	0.15%
Line of credit facility, remaining borrowing capacity		$ 0	$ 0
Revolving Credit Facility \| Revolving Credit Facility, Amended and Restated \| Minimum
Debt Instrument [Line Items]
Commitment fee		0.15%
Revolving Credit Facility \| Revolving Credit Facility, Amended and Restated \| Maximum
Debt Instrument [Line Items]
Commitment fee		0.30%
Unsecured Debt \| Unsecured Term Loan
Debt Instrument [Line Items]
Commitment fee		0.15%	0.15%
Debt instrument, face amount	$ 400,000,000
Number of tranches \| tranche	2
Unsecured Debt \| Unsecured Term Loan \| Minimum
Debt Instrument [Line Items]
Commitment fee	0.15%
Unsecured Debt \| Unsecured Term Loan \| Maximum
Debt Instrument [Line Items]
Commitment fee	0.25%
Unsecured Debt \| Term Loan, Tranche One
Debt Instrument [Line Items]
Debt instrument, term	5 years
Debt instrument, face amount	$ 250,000,000
Unsecured Debt \| Term Loan, Tranche Two
Debt Instrument [Line Items]
Debt instrument, term	5 years 6 months
Line of credit facility, remaining borrowing capacity		$ 48,000,000	$ 48,000,000
Debt instrument, face amount	$ 150,000,000