CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Mar. 31, 2022		26,982,000
Beginning balance at Mar. 31, 2022	$ 1,538,825	$ 270	$ 210,825	$ 1,352,685	$ (24,955)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (in shares)		1,000
Stock-based compensation	3,735		3,735
Shares withheld for taxes	(43)		(43)
Repurchases of common stock (Note 8) (in shares)		(384,000)
Repurchases of common stock (Note 8)	(99,993)	$ (4)		(99,989)
Net income	44,849			44,849
Total other comprehensive (loss) income	(14,966)				(14,966)
Ending balance (in shares) at Jun. 30, 2022		26,599,000
Ending balance at Jun. 30, 2022	1,472,407	$ 266	214,517	1,297,545	(39,921)
Beginning balance (in shares) at Mar. 31, 2022		26,982,000
Beginning balance at Mar. 31, 2022	$ 1,538,825	$ 270	210,825	1,352,685	(24,955)
Increase (Decrease) in Stockholders' Equity
Repurchases of common stock (Note 8) (in shares)	(685,075)
Repurchases of common stock (Note 8)	$ (194,862)
Net income	425,035
Total other comprehensive (loss) income	(15,321)
Ending balance (in shares) at Dec. 31, 2022		26,358,000
Ending balance at Dec. 31, 2022	1,769,172	$ 264	226,320	1,582,864	(40,276)
Beginning balance (in shares) at Jun. 30, 2022		26,599,000
Beginning balance at Jun. 30, 2022	1,472,407	$ 266	214,517	1,297,545	(39,921)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (in shares)		1,000
Stock-based compensation	6,779		6,779
Shares issued upon vesting (in shares)		27,000
Shares issued upon vesting	1,046		1,046
Exercise of stock options (in shares)		27,000
Exercise of stock options	1,830		1,830
Shares withheld for taxes	(5,059)		(5,059)
Repurchases of common stock (Note 8) (in shares)		(173,000)
Repurchases of common stock (Note 8)	(50,247)	$ (1)		(50,246)
Net income	101,524			101,524
Total other comprehensive (loss) income	(12,441)				(12,441)
Ending balance (in shares) at Sep. 30, 2022		26,481,000
Ending balance at Sep. 30, 2022	1,515,839	$ 265	219,113	1,348,823	(52,362)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation	7,479		7,479
Shares issued upon vesting (in shares)		2,000
Exercise of stock options (in shares)		1,000
Exercise of stock options	40		40
Shares withheld for taxes	(312)		(312)
Repurchases of common stock (Note 8) (in shares)		(127,000)
Repurchases of common stock (Note 8)	(44,622)	$ (1)		(44,621)
Net income	278,662			278,662
Total other comprehensive (loss) income	12,086				12,086
Ending balance (in shares) at Dec. 31, 2022		26,358,000
Ending balance at Dec. 31, 2022	$ 1,769,172	$ 264	226,320	1,582,864	(40,276)
Beginning balance (in shares) at Mar. 31, 2023	26,176,000	26,176,000
Beginning balance at Mar. 31, 2023	$ 1,765,733	$ 262	232,932	1,571,574	(39,035)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (in shares)		1,000
Stock-based compensation	6,877		6,877
Shares issued upon vesting (in shares)		3,000
Exercise of stock options (in shares)		8,000
Exercise of stock options	548		548
Shares withheld for taxes	(698)		(698)
Repurchases of common stock (Note 8) (in shares)		(52,000)
Repurchases of common stock (Note 8)	(25,469)	$ (1)		(25,468)
Excise taxes related to repurchases of common stock	(123)			(123)
Net income	63,552			63,552
Total other comprehensive (loss) income	(8,299)				(8,299)
Ending balance (in shares) at Jun. 30, 2023		26,136,000
Ending balance at Jun. 30, 2023	$ 1,802,121	$ 261	239,659	1,609,535	(47,334)
Beginning balance (in shares) at Mar. 31, 2023	26,176,000	26,176,000
Beginning balance at Mar. 31, 2023	$ 1,765,733	$ 262	232,932	1,571,574	(39,035)
Increase (Decrease) in Stockholders' Equity
Repurchases of common stock (Note 8) (in shares)	(595,660)
Repurchases of common stock (Note 8)	$ (310,635)
Net income	632,018
Total other comprehensive (loss) income	$ (3,339)
Ending balance (in shares) at Dec. 31, 2023	25,650,000	25,650,000
Ending balance at Dec. 31, 2023	$ 2,104,190	$ 256	255,994	1,890,314	(42,374)
Beginning balance (in shares) at Jun. 30, 2023		26,136,000
Beginning balance at Jun. 30, 2023	1,802,121	$ 261	239,659	1,609,535	(47,334)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation (in shares)		1,000
Stock-based compensation	9,802		9,802
Shares issued upon vesting (in shares)		24,000
Shares issued upon vesting	1,165		1,165
Exercise of stock options (in shares)		8,000
Exercise of stock options	533		533
Shares withheld for taxes	(7,759)		(7,759)
Repurchases of common stock (Note 8) (in shares)		(347,000)
Repurchases of common stock (Note 8)	(185,469)	$ (3)		(185,466)
Excise taxes related to repurchases of common stock	(1,693)			(1,693)
Net income	178,547			178,547
Total other comprehensive (loss) income	(2,117)				(2,117)
Ending balance (in shares) at Sep. 30, 2023		25,822,000
Ending balance at Sep. 30, 2023	1,795,130	$ 258	243,400	1,600,923	(49,451)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation	11,846		11,846
Shares issued upon vesting (in shares)		2,000
Exercise of stock options (in shares)		22,000
Exercise of stock options	1,444		1,444
Shares withheld for taxes	(696)		(696)
Repurchases of common stock (Note 8) (in shares)		(196,000)
Repurchases of common stock (Note 8)	(99,697)	$ (2)		(99,695)
Excise taxes related to repurchases of common stock	(833)			(833)
Net income	389,919			389,919
Total other comprehensive (loss) income	$ 7,077				7,077
Ending balance (in shares) at Dec. 31, 2023	25,650,000	25,650,000
Ending balance at Dec. 31, 2023	$ 2,104,190	$ 256	$ 255,994	$ 1,890,314	$ (42,374)