Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 835
-SubTopic 30
-Section 55
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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Definition

Number Of Derivatives Terminated

+ References

No definition available.

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Long-Term Debt And Shareholders' Equity (Debt Narrative) (Details)	3 Months Ended
	Jun. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2020 derivative_instrument	Mar. 31, 2020 derivative
Debt Instrument [Line Items]
Number of derivatives terminated			2	2
Senior Notes \| 3.50% Senior Notes
Debt Instrument [Line Items]
Repayments of debt	$ 219,000,000
Debt interest rate	3.50%
Senior Notes \| 3.35% Senior Notes
Debt Instrument [Line Items]
Repayments of debt	$ 210,000,000
Debt interest rate	3.35%
Subordinated Debt \| 3.35% Senior Notes
Debt Instrument [Line Items]
Debt interest rate		3.25%
Subordinated Debt \| Subordinated Notes Interest Rate 3.25%
Debt Instrument [Line Items]
Face amount of debt		$ 500,000,000