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

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

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.

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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=64837297&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=64837297&loc=SL5624177-113959

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- Definition

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

+ References

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.

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)			12 Months Ended
	Jun. 24, 2016	Sep. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount				$ 350,000,000	$ 200,000,000
Realized (gains) losses on interest rate hedges reclassified to earnings				492,000	0	$ 0
Interest Rate Cap
Derivative Instruments Gain Loss [Line Items]
Increase (Decrease) in Fair Value of Interest Rate Fair Value Hedging Instruments				24,000
Interest Rate Swap
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount				$ 150,000,000
Derivative, maturity date				Jun. 17, 2021
Cash Flow Hedge
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount				$ 150,000,000	200,000,000
Derivative, strike rate for the interest rate swap contract	1.145%
Cash Flow Hedge \| Interest Rate Cap
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount		$ 200,000,000			$ 200,000,000
Derivative, maturity date		Oct. 17, 2017
Cash Flow Hedge \| Interest Rate Swap
Derivative Instruments Gain Loss [Line Items]
Derivative, notional amount	$ 150,000,000			$ 150,000,000
Derivative, maturity date	Jun. 17, 2021
Cash Flow Hedge \| Interest Rate Swaps and Caps \| Scenario, Forecast
Derivative Instruments Gain Loss [Line Items]
Reclassified out of accumulated other comprehensive income to earnings, amount			$ 292,000
Cash Flow Hedge \| 1-month LIBOR
Derivative Instruments Gain Loss [Line Items]
Interest rate cap strike rate		3.00%