Variable Interest Entities (Summary of Key Terms of NMTC Transactions) (Details) - Primary Beneficiary - USD ($) $ in Millions	Oct. 02, 2019	Dec. 22, 2017	Mar. 21, 2017
Variable Interest Entity [Line Items]
Loan Amount	$ 4.8	$ 10.4	$ 6.7
Interest Rate on Loan	1.00%	1.00%	1.00%
US Bancorp Investment
Variable Interest Entity [Line Items]
Financial support to other entity	$ 2.2	$ 5.1	$ 3.3
Loan to Unicom
Variable Interest Entity [Line Items]
Interest Rate on Loan	1.80%		0.70%
Financial support to other entity	$ 6.7	$ 14.7	$ 9.8
Loan to Unicom \| Minimum
Variable Interest Entity [Line Items]
Interest Rate on Loan		0.70%
Loan to Unicom \| Maximum
Variable Interest Entity [Line Items]
Interest Rate on Loan		1.20%

Variable Interest Entity, Financial or Other Support, Amount To Other Entity

No definition available.

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- Definition

Variable Interest Entity, Financial or Other Support, Interest Rate Percentage

+ References

No definition available.

+ Details

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- Definition

The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=SL6759159-111685

+ 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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- Details

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- Details

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- Details

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