Debt Instrument, Amortization Period After Interest Only Payments Period

No definition available.

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- Definition

Debt Instrument, Base Rate Margin

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties pledged to secure a debt instrument.

+ References

No definition available.

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- Definition

Debt Instrument, Interest Only Payments Term

+ References

No definition available.

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- Definition

Represents the amount by which the borrowing capacity of the line of credit may be increased at the entity's option, subject to certain conditions, under the terms of the credit agreement.

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Percentage Bearing Variable Interest Rates that Had Been Converted to Fixed Interest Rates

+ References

No definition available.

+ Details

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- Definition

Number Of Debt Instrument

+ References

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- 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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

+ Details

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

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- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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Balance Type:	debit
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- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

+ References

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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DEBT - Narrative (Details)					6 Months Ended			12 Months Ended
DEBT - Narrative (Details)	May 16, 2018 USD ($)	Apr. 02, 2018 USD ($) Loan	Feb. 15, 2018 USD ($)	Sep. 26, 2017 USD ($)	Jun. 30, 2018 USD ($) Property	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Jan. 15, 2016 USD ($)	Apr. 08, 2015 USD ($)	Apr. 07, 2015 USD ($)	Sep. 05, 2013 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate for all borrowings, after giving effect to interest rate derivatives (as a percent)					4.20%			3.89%
Number of properties that served as collateral for loans \| Property					51
Principal payments on debt					$ 337,297,000		$ 178,178,000
Long-term debt					950,497,000	$ 868,236,000		$ 868,236,000
Secured and unsecured debt \| Total term loans
Debt Instrument [Line Items]
Long-term debt					910,800,000
Secured debt \| Total term loans
Debt Instrument [Line Items]
Long-term debt					310,800,000
Secured debt \| Non-recourse Loan \| Metabank
Debt Instrument [Line Items]
Debt instrument, face amount							$ 47,600,000.0
Amount drawn on secured debt						$ 47,600,000
Fixed interest rate						4.44%		4.44%
Debt instrument, interest only payments term								18 months
Debt instrument, amortization period after interest only payments period								25 years
Unsecured debt \| $450 Million Senior Unsecured Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount					450,000,000.0	$ 450,000,000.0		$ 450,000,000.0
Maximum borrowing capacity					450,000,000.0				$ 450,000,000.0
Maximum increase in borrowing capacity available through accordion feature option					150,000,000.0
Unsecured debt \| $300 Million Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, face amount									300,000,000.0
Amount available for borrowing					255,000,000
Long-term debt					$ 45,000,000
Unsecured debt \| $150 Million Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount									$ 150,000,000
Fixed interest rate					3.79%
Long-term debt					$ 150,000,000
Unsecured debt \| 2015 Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount										$ 140,000,000.0	$ 125,000,000.0
Principal payments on debt			$ 140,000,000
Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount				$ 225,000,000.0
Maximum increase in borrowing capacity available through accordion feature option				$ 175,000,000.0
Debt instrument, effective interest rate					3.84%
Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount			225,000,000.0
Maximum increase in borrowing capacity available through accordion feature option			150,000,000.0
Debt instrument, effective interest rate					4.14%
Amount drawn on unsecured debt	$ 85,000,000		$ 140,000,000
Mortgage loans \| Western Alliance Bank
Debt Instrument [Line Items]
Debt instrument, effective interest rate		5.39%
Principal payments on debt		$ 23,900,000
Number of debt instrument \| Loan		4
Option One \| Minimum \| LIBOR \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				1.45%
Option One \| Minimum \| LIBOR \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.80%
Option One \| Maximum \| LIBOR \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				2.20%
Option One \| Maximum \| LIBOR \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			2.55%
Option Two \| LIBOR \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				1.00%
Option Two \| LIBOR \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.00%
Option Two \| Federal Funds Rate \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				0.50%
Option Two \| Federal Funds Rate \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			0.50%
Option Two \| Minimum \| Base rate \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				0.45%
Option Two \| Minimum \| Base rate \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			0.80%
Option Two \| Maximum \| Base rate \| Unsecured debt \| 2017 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate				1.20%
Option Two \| Maximum \| Base rate \| Unsecured debt \| 2018 Term Loan
Debt Instrument [Line Items]
Debt basis spread on variable rate			1.55%
Designated as hedges \| Interest rate swaps
Debt Instrument [Line Items]
Notional Amount					$ 475,000,000	275,000,000		275,000,000
Designated as hedges \| Cash flow hedges \| Interest rate swaps
Debt Instrument [Line Items]
Notional Amount												$ 75,000,000.0
Designated as hedges \| Cash flow hedges \| Interest rate swaps \| LIBOR
Debt Instrument [Line Items]
Fixed interest rate					2.04%
Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, effective interest rate					3.89%
Revolving Credit Facility \| Option One \| Minimum \| LIBOR
Debt Instrument [Line Items]
Debt basis spread on variable rate					1.50%
Revolving Credit Facility \| Option One \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt basis spread on variable rate					2.25%
Revolving Credit Facility \| Option Two \| LIBOR
Debt Instrument [Line Items]
Debt basis spread on variable rate					1.00%
Revolving Credit Facility \| Option Two \| Federal Funds Rate
Debt Instrument [Line Items]
Debt basis spread on variable rate					0.50%
Revolving Credit Facility \| Option Two \| Minimum
Debt Instrument [Line Items]
Debt instrument, base rate margin					0.50%
Revolving Credit Facility \| Option Two \| Maximum
Debt Instrument [Line Items]
Debt instrument, base rate margin					1.25%
Fair Value
Debt Instrument [Line Items]
Debt with variable interest rates that had been converted to fixed interest rates					$ 275,000,000	$ 75,000,000		$ 75,000,000