Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated Other Comprehensive Income (Loss)	Unrealized investment gain	Currency Translation Adjustments	Treasury stock	Noncontrolling interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment resulting from changes in accounting principles		$ 105,803	$ 977,215	$ 8,348,381	$ (62,172)	$ 289,714	$ (351,886)	$ (3,058,425)	$ 14,995
Beginning of period at Dec. 31, 2020		105,803	977,215	8,348,381	(62,172)	289,714	(351,886)	(3,058,425)	14,995
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units issued			(525)
Restricted stock units expensed			11,598
Net income before noncontrolling interests	$ 231,716			229,525					2,191
Dividends ($0.09 and $0.08, per share, respectively)				(21,285)
Change in unrealized losses on securities without an allowance for expected credit losses	(90,130)					(100,485)
Change in unrealized gains on securities with an allowance for expected credit losses						10,355
Net change in period	4,050						4,050
Stock exercised/vested								248
Stock repurchased								(29,683)
Contributions (distributions)									(1,502)
Other comprehensive loss, net of tax	$ (86,080)				(86,080)		4,050		0
End of period at Mar. 31, 2021			988,288	8,556,621	(148,252)	199,584	(347,836)	(3,087,860)	15,684
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock dividends, per share, cash paid (in dollars per share)	$ 0.08
Cumulative effect adjustment resulting from changes in accounting principles			988,288	8,556,621	(148,252)	199,584	(347,836)	(3,087,860)	15,684
Cumulative effect adjustment resulting from changes in accounting principles	$ 6,667,730	105,803	981,104	9,015,135	(281,955)	90,900	(372,855)	(3,167,076)	14,719
Beginning of period at Dec. 31, 2021	6,667,730	$ 105,803	981,104	9,015,135	(281,955)	90,900	(372,855)	(3,167,076)	14,719
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units issued			(530)
Restricted stock units expensed			11,438
Net income before noncontrolling interests	593,030			590,638					2,392
Dividends ($0.09 and $0.08, per share, respectively)				(22,983)
Change in unrealized losses on securities without an allowance for expected credit losses	(423,545)					(423,839)
Change in unrealized gains on securities with an allowance for expected credit losses						293
Net change in period	56,272						56,272
Stock exercised/vested								203
Stock repurchased								0
Contributions (distributions)									6,186
Other comprehensive loss, net of tax	(367,273)				(367,273)		56,272		(1)
End of period at Mar. 31, 2022	$ 6,887,799		992,012	9,582,790	(649,229)	(332,646)	(316,583)	(3,166,873)	23,296
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock dividends, per share, cash paid (in dollars per share)	$ 0.09
Cumulative effect adjustment resulting from changes in accounting principles	$ 6,887,799		$ 992,012	$ 9,582,790	$ (649,229)	$ (332,646)	$ (316,583)	$ (3,166,873)	$ 23,296