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Fair Value Measurements (Narrative) (Details) € in Millions, gal in Millions	1 Months Ended	12 Months Ended
	May 31, 2021 USD ($)	Dec. 31, 2022 USD ($) $ / gal € / shares gal	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 EUR (€) $ / gal € / shares
Derivatives Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Volume | gal		7.3
Fair value hedge liabilities		$ 638,000
Fair value hedge assets			$ 630,000
Reclassification of derivative (gains) losses to earnings net of tax		10,629,000
Debt instrument, face amount	$ 325,000,000
Maturity date	Jun. 01, 2029
Fair Value, Inputs, Level 1 [Member]
Derivatives Fair Value [Line Items]
Fair value of debt		$ 252,655,000
Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal		2.29			2.29
Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal		3.95			3.95
Fuel Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Derivative underlying hedge percent		80.00%
Reclassification of derivative (gains) losses to earnings net of tax		$ 10,629,000	$ 6,481,000	$ (5,825,000)
Foreign Currency Exchange Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Fair value hedge liabilities		6,000
Fair value hedge assets		831,000
Reclassification of derivative (gains) losses to earnings net of tax		(116,000)
Derivative notional amount | €					€ 28.9
Reclassification of derivative (gains) losses to earnings net of cash settlements and taxes		$ 155,000
Foreign Currency Exchange Hedge Contracts [Member] | Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares		0.99			0.99
Foreign Currency Exchange Hedge Contracts [Member] | Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares		1.13			1.13

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