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

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

Interest rate cash flow hedge gain loss reclassified to earnings net of mark to market.

+ References

No definition available.

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

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- Definition

Floor rate on an interest rate derivative such as an interest rate floor or collar. If market rates falls below the floor rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

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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.

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No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

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No definition available.

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

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- Definition

The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

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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

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)			3 Months Ended	12 Months Ended
	Nov. 17, 2017	Jun. 24, 2016	Mar. 31, 2018	Mar. 31, 2019	Jan. 04, 2018	Dec. 31, 2017	Apr. 17, 2017
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount			$ 250,000,000			$ 250,000,000
Derivative, strike rate for the interest rate swap contract		1.145%					1.1325%
Realized gains on interest rate hedges reclassified to earnings			174,000
Unsecured Term Loan
Derivative Instruments Gain Loss [Line Items]
Secured credit facility borrowing capacity	$ 100,000,000
Cash Flow Hedge
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount			250,000,000			200,000,000
Freestanding Derivatives \| Other Income (Expense)
Derivative Instruments Gain Loss [Line Items]
Recognition of hedge ineffectiveness			52,000
Interest Rate Swap
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount		$ 150,000
Derivative, maturity date		Jun. 17, 2021
Recognition of hedge ineffectiveness			0
Interest Rate Swap \| Cash Flow Hedge
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount			150,000,000			150,000,000
Interest Rate Collar \| Cash Flow Hedge
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount	$ 100,000,000		$ 100,000,000			50,000,000
Derivative, maturity date	Nov. 17, 2024
Interest rate cap strike rate	2.00%
Floor interest rate	1.25%
Interest Rate Collar \| Cash Flow Hedge \| Designated
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount	$ 50,000,000
Interest Rate Collar \| Freestanding Derivatives
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount	$ 50,000,000					$ 50,000,000
Interest Rate Collar \| Freestanding Derivatives \| Designated
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount					$ 50,000,000
Interest Rate Swaps and Caps \| Cash Flow Hedge \| Scenario, Forecast
Derivative Instruments Gain Loss [Line Items]
Reclassified out of accumulated other comprehensive income to earnings, amount				$ 1,608,000