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

No definition available.

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- Definition

The number of building under lease agreement.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

+ Details

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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ 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

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Derivative Instruments and Hedging Activities - Notional principal amounts (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020 USD ($) building	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) building	Mar. 31, 2019 USD ($)	Apr. 01, 2020 USD ($)	Sep. 30, 2019 USD ($)
Two Buildings on Existing Campus
Derivative Instruments and Hedging Activities
Unrealized gain (loss) on derivative	$ 5,000		$ 3,600
Number of building under lease \| building	2		2
Maximum
Derivative Instruments and Hedging Activities
Term of derivative contract			5 years
Instruments designated as accounting hedges: \| Foreign currency forwards
Derivative Instruments and Hedging Activities
Notional principal outstanding derivative instruments	$ 137,113		$ 137,113			$ 143,164
Instruments designated as accounting hedges: \| Interest Rate Swaps
Derivative Instruments and Hedging Activities
Notional principal outstanding derivative instruments	95,000		95,000			95,000
Instruments designated as accounting hedges: \| Interest Rate Swaps \| Credit Facility \| Subsequent event
Derivative Instruments and Hedging Activities
Notional principal outstanding derivative instruments					$ 550,000
Instruments not designated as accounting hedges: \| Foreign currency forwards
Derivative Instruments and Hedging Activities
Notional principal outstanding derivative instruments	34,303		34,303			24,220
Notional principal outstanding derivative instruments designed to manage exposure	34,100		34,100			$ 14,000
Unrealized gain (loss) on derivative	$ (2,600)	$ 300	$ (1,800)	$ 0