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Financing: Revolving Credit Facility and CP Program (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Net (payments) borrowings of Revolving Credit Facility and CP Program	$ (18,170)	$ (30,375)
Commercial Paper
Short-term interest rate	0.23%

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- Definition

Net (payments) borrowings of Revolving Credit Facility and Commercial Paper Program

+ References

No definition available.

+ Details

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Details

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