Note 3 - Stock-based Compensation - RSU Summary (Details) shares in Thousands	9 Months Ended
	Sep. 30, 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	31
Granted, weighted average (in dollars per share) | $ / shares	$ 643.98
Vested (in shares) | shares	(39)
Vested, weighted average (in dollars per share) | $ / shares	$ 374.15
Forfeited (in shares) | shares	(4)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 471.15
Balance (in shares) | shares	90
Outstanding, weighted average (in dollars per share) | $ / shares	$ 505.64
PSUs and MPSUs [Member]
Balance (in shares) | shares	482
Outstanding, weighted average (in dollars per share) | $ / shares	$ 397,770
Granted (in shares) | shares	344	[1]
Granted, weighted average (in dollars per share) | $ / shares	$ 593.33
Vested (in shares) | shares	(150)
Vested, weighted average (in dollars per share) | $ / shares	$ 272.21
Forfeited (in shares) | shares	(1)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 400.96
Balance (in shares) | shares	675
Outstanding, weighted average (in dollars per share) | $ / shares	$ 525.43
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	(1)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 270.15
Balance (in shares) | shares	938
Outstanding, weighted average (in dollars per share) | $ / shares	$ 203.32
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	375
Granted, weighted average (in dollars per share) | $ / shares	$ 597.56
Vested (in shares) | shares	(752)
Vested, weighted average (in dollars per share) | $ / shares	$ 125.04
Forfeited (in shares) | shares	(6)
Forfeited, weighted average (in dollars per share) | $ / shares	$ 419.22
Balance (in shares) | shares	1,703
Outstanding, weighted average (in dollars per share) | $ / shares	$ 346.88

[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.