Note 3 - Stock-based Compensation - RSU Summary (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Time-Based RSUs [Member]
Balance (in shares) | shares	102
Outstanding, weighted average (in dollars per share) | $ / shares	$ 411.11
Granted (in shares) | shares	21
Granted, weighted average (in dollars per share) | $ / shares	$ 632.98
Vested (in shares) | shares	(14)
Vested, weighted average (in dollars per share) | $ / shares	$ 372.3
Forfeited (in shares) | shares	(2)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 467.3
Balance (in shares) | shares	107
Outstanding, weighted average (in dollars per share) | $ / shares	$ 458.67
PSUs and MPSUs [Member]
Balance (in shares) | shares	482
Outstanding, weighted average (in dollars per share) | $ / shares	$ 397,770
Granted (in shares) | shares	240	[1]
Granted, weighted average (in dollars per share) | $ / shares	$ 609.22
Vested (in shares) | shares	(57)
Vested, weighted average (in dollars per share) | $ / shares	$ 287.31
Forfeited (in shares) | shares	0
Forfeited, weighted average (in dollars per share) | $ / shares	$ 0
Balance (in shares) | shares	665
Outstanding, weighted average (in dollars per share) | $ / shares	$ 489.68
MSUs [Member]
Balance (in shares) | shares	1,502
Outstanding, weighted average (in dollars per share) | $ / shares	$ 152.89
Granted (in shares) | shares	0
Granted, weighted average (in dollars per share) | $ / shares	$ 0
Vested (in shares) | shares	(563)
Vested, weighted average (in dollars per share) | $ / shares	$ 68.48
Forfeited (in shares) | shares	0
Forfeited, weighted average (in dollars per share) | $ / shares	$ 0
Balance (in shares) | shares	939
Outstanding, weighted average (in dollars per share) | $ / shares	$ 203.38
Time-Based RSUs PSUs MSUs [Member]
Balance (in shares) | shares	2,086
Outstanding, weighted average (in dollars per share) | $ / shares	$ 222.04
Granted (in shares) | shares	261
Granted, weighted average (in dollars per share) | $ / shares	$ 610.67
Vested (in shares) | shares	(634)
Vested, weighted average (in dollars per share) | $ / shares	$ 94.76
Forfeited (in shares) | shares	(2)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 423.45
Balance (in shares) | shares	1,711
Outstanding, weighted average (in dollars per share) | $ / shares	$ 330.53

[1] Amount reflects the number of awards that may ultimately be earned based on management's probability assessment of the achievement of performance conditions at each reporting period.