Financial Instruments: Derivatives and Hedging (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Nov. 30, 2021
Financial Instruments: Derivatives and Hedging
Hedged amount of portion of the future LIBOR-based rate risk	$ 8,100
Interest reclassified from accumulated other comprehensive income into interest expense	2,900
Amount estimated to be reclassified into earnings within next 12 months	900
Cash flow hedges
Financial Instruments: Derivatives and Hedging
Unrealized gains or losses on derivative financial instruments in accumulated other comprehensive income	18,300
JPM Term Loan
Financial Instruments: Derivatives and Hedging
Hedged amount of portion of the future LIBOR-based rate risk	100,000
2017 Interest Rate Swap
Financial Instruments: Derivatives and Hedging
Fair Value	4,600
2017 Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 400,000
Strike Rate (as a percent)	1.12%
Fair Value	$ 4,645
2013 BMO Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 220,000
Strike Rate (as a percent)	2.32%
Fair Value	$ (1,292)
2019 JPM Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 100,000
Strike Rate (as a percent)	2.44%
Fair Value	$ (1,837)
2019 BMO Interest Rate Swap \| Cash flow hedges
Financial Instruments: Derivatives and Hedging
Notional Value	$ 220,000
Strike Rate (as a percent)	2.39%
Fair Value	$ (5,003)
2019 BMO Interest Rate Swap \| Cash flow hedges \| Forecast
Financial Instruments: Derivatives and Hedging
Notional Value		$ 165,000

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

Fixed interest rate related to the interest rate derivative.

+ 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

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- Definition

Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

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- Definition

Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 1
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-Paragraph 4
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 17A
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL34724391-108580

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