Financial Instruments (Tables)	12 Months Ended
Dec. 31, 2021
Financial Instruments [Abstract]
Carrying Value, Fair Value And Hierarchy Of Financial Instruments	The following shows the carrying value, fair value and the hierarchy for our financial instruments as of December 31, 2021 (in thousands): Fair Value Measure Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investments of deferred compensation plans held in trust$ 98,884 $ 98,884 $ - $ -Long-term debt 185,000 - 185,000 - The following shows the carrying value, fair value and the hierarchy for our financial instruments as of December 31, 2020 (in thousands): Fair Value Measure Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Investments of deferred compensation plans held in trust$ 88,811 $ 88,811 $ - $ -

Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13467-108611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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