CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock.	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Common Class A [Member]	Total
Balance at Dec. 31, 2020	$ 7	$ 1,047,052	$ 2,342,329		$ 3,389,388
Balance (in shares) at Dec. 31, 2020	70,906
Changes in stockholders' equity
Net income			376,868		376,868
Stock based compensation		4,001			4,001
Stock based compensation (in shares)	707
Issuance of common stock in settlement of directors' fees		51			51
Issuance of common stock in settlement of directors' fees (in shares)	1
Common stock dividends			(14,375)		(14,375)
Repurchase of common stock		(288,519)		$ (288,519)	(288,519)
Repurchase of common stock (in shares)	(4,653)			(4,653)
Balance at Mar. 31, 2021	$ 7	762,585	2,704,822		3,467,414
Balance (in shares) at Mar. 31, 2021	66,961
Balance at Dec. 31, 2021	$ 6	125,396	3,292,923		3,418,325
Balance (in shares) at Dec. 31, 2021	56,867
Changes in stockholders' equity
Net income			173,593		173,593
Stock based compensation		2,471			2,471
Stock based compensation (in shares)	794
Issuance of common stock in settlement of directors' fees		51			51
Issuance of common stock in settlement of directors' fees (in shares)	1
Common stock dividends			(11,425)		(11,425)
Repurchase of common stock		$ (127,918)	(13,494)	$ (141,412)	(141,412)
Repurchase of common stock (in shares)	(2,320)			(2,320)
Balance at Mar. 31, 2022	$ 6		$ 3,441,597		$ 3,441,603
Balance (in shares) at Mar. 31, 2022	55,342