Debt instrument treasury rate basis points for redemption.

No definition available.

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- Definition

Redemption price, percentage of principal amount.

+ References

No definition available.

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- Definition

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

+ References

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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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Senior Notes (Summary of Senior Notes) (Parenthetical) (Details) - USD ($) $ in Thousands			1 Months Ended	6 Months Ended
	Feb. 15, 2030	Oct. 27, 2017	Jul. 31, 2016	Jun. 30, 2021	Dec. 31, 2020	May 31, 2020	Oct. 31, 2017	Jul. 31, 2014
Debt Instrument [Line Items]
Long-term Debt				$ 1,112,941	$ 1,112,409
Senior notes 4.25% due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage				4.25%
Long-term Debt								$ 300,000
Debt instrument, maturity date				Jul. 31, 2024
Redemption price, percentage of principal amount				100.00%
Additional issuance of long-term debt			$ 200,000
Senior notes 4.00% due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage				4.00%
Long-term Debt						$ 400,000
Debt instrument, maturity date				May 31, 2030
Senior notes 4.00% due 2030 [Member] \| After February 15, 2030 [Member]
Debt Instrument [Line Items]
Redemption price, percentage of principal amount				100.00%
Senior notes 4.00% due 2030 [Member] \| Measurement Input, Discount Rate [Member] \| Prior to February 15, 2030 [Member]
Debt Instrument [Line Items]
Redemption at treasury rate basis point				0.50%
Senior notes 4.00% due 2030 [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Redemption price, percentage of principal amount	100.00%
Senior notes 5.20% due 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument Interest Rate Stated Percentage				5.20%
Long-term Debt							$ 200,000
Debt instrument, maturity date				Oct. 31, 2047
Redemption price, percentage of principal amount				100.00%
Additional issuance of long-term debt		$ 25,000