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Fair Value Measurements (Narrative) (Details) $ in Thousands, gal in Millions	3 Months Ended
	Mar. 31, 2025 USD ($) Swap $ / gal € / shares gal	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Derivatives Fair Value [Line Items]
Debt instrument, face amount	$ 325,000
Fair Value, Inputs, Level 1 [Member]
Derivatives Fair Value [Line Items]
Fair value of debt	$ 294,300
Fuel Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Derivative underlying hedge percent	80.00%
Derivative, nonmonetary notional amount, volume | gal	16.4
Reclassification of derivative gain (losses) to earnings net of tax	$ 120	$ (122)
Fair value hedge liabilities	$ 300		$ 1,100
Fuel Hedge Contracts [Member] | Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal	2.18
Fuel Hedge Contracts [Member] | Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | $ / gal	2.9
Foreign Currency Exchange Hedge Contracts [Member]
Derivatives Fair Value [Line Items]
Reclassification of derivative gain (losses) to earnings net of tax		36
Reclassification of derivative (gains) losses to earnings net of cash settlements and taxes		$ 36
Foreign Currency Exchange Hedge Contracts [Member] | Minimum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares	1.01
Foreign Currency Exchange Hedge Contracts [Member] | Maximum [Member]
Derivatives Fair Value [Line Items]
Fixed price range | € / shares	1.13
Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Reclassification of derivative gain (losses) to earnings net of tax	$ 68
Derivative notional amount	75,000
Fair value hedge liabilities	$ 64
Derivative, maturity date	Aug. 24, 2026
Floating-rate debt to weighted average fixed interest rate	11.62%
Derivative, average fixed interest rate	3.87%
Number of interest rate swaps | Swap	2

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