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

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
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- Definition

Fixed interest rate related to the interest rate derivative.

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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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- Definition

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

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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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-Publisher FASB
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Interest Rate Swaps - Interest rate derivatives and their fair values (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 20, 2018	Apr. 05, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of other comprehensive income to interest expense		$ (110)	$ 0	$ 0
Forecast
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassification of other comprehensive income to interest expense	$ 2,100
Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative					$ 400,000	$ 400,000
Interest Rate Swap \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		1,000,000	400,000
Fair value		2,343	1,449
Swap instrument one matures on December 17, 2021 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 25,000	25,000
Fixed Rate Per annum		1.989%
Expiration Date		Dec. 17, 2021
Fair value		$ 331	100
Swap instrument two matures on December 17, 2021 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 100,000	100,000
Fixed Rate Per annum		1.989%
Expiration Date		Dec. 17, 2021
Fair value		$ 1,318	401
Swap instrument three matures on December 17, 2021 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 75,000	75,000
Fixed Rate Per annum		1.989%
Expiration Date		Dec. 17, 2021
Fair value		$ 990	298
Swap instrument one matures on April 27, 2022 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 50,000	50,000
Fixed Rate Per annum		2.033%
Expiration Date		Apr. 27, 2022
Fair value		$ 667	158
Swap instrument two matures on April 27, 2022 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 100,000	100,000
Fixed Rate Per annum		2.029%
Expiration Date		Apr. 27, 2022
Fair value		$ 1,341	337
Swap instrument three matures on April 27, 2022 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 50,000	50,000
Fixed Rate Per annum		2.033%
Expiration Date		Apr. 27, 2022
Fair value		$ 666	$ 155
Swap instrument one matures on December 17, 2023 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 100,000
Fixed Rate Per annum		2.617%
Expiration Date		Dec. 17, 2023
Fair value		$ (782)
Swap instrument two matures on December 17, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 200,000
Fixed Rate Per annum		2.636%
Expiration Date		Dec. 17, 2023
Fair value		$ (722)
Swap instrument one matures on April 27, 2024 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 100,000
Fixed Rate Per annum		2.621%
Expiration Date		Apr. 27, 2024
Fair value		$ (818)
Swap instrument two matures on April 27, 2024 \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of derivative		$ 200,000
Fixed Rate Per annum		2.642%
Expiration Date		Apr. 27, 2024
Fair value		$ (648)