Stock-Based Compensation (Changes in Stock Appreciation Rights) (Details) - Stock Appreciation Rights (SARs) [Member] $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $	$ 8.2
Shares
Outstanding awards as of beginning of period (in shares) | shares	679,500
Granted (in shares) | shares	75,700
Exercised (in shares) | shares	(269,400)
Outstanding awards as of end of period (in shares) | shares	478,300
Exercisable at end of period (in shares) | shares	311,700
Weighted-Average Exercise Price per Share
Outstanding awards as of beginning of period (in usd per share) | $ / shares	$ 205.41
Granted (in usd per share) | $ / shares	328.65
Exercised (in usd per share) | $ / shares	179.61
Outstanding as of end of period (in shares) | $ / shares	241.61
Exercisable at end of period, Weighted-Average Exercise Price per Share (in usd per share) | $ / shares	$ 212.22
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period | shares	(7,500)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value | $ / shares	$ 243.87