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Long-term Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term debt | $ 598,848 | $ 642,941
Revolving Credit Facility [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt | $ 0 | $ 44,678
4.10% Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Senior notes, interest rate | 4.10% | 4.10%
Long-term debt | $ 348,848 | $ 348,263
3.78% Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Senior notes, interest rate | 3.78% | 3.78%
Long-term debt | $ 250,000 | $ 250,000

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- 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 + Details
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- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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