Schedule II - Condensed Financial Information of Registrant - Balance Sheet (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Assets
Total investments	$ 27,292,927	$ 26,588,156
Cash	855,118	858,668	$ 906,448
Investment in operating affiliates	964,604	1,135,655
Other assets	2,919,605	2,453,849
Total assets	47,990,507	45,100,945	43,282,297
Liabilities
Senior notes	2,725,410	2,724,394
Other liabilities	1,367,068	1,329,742
Total liabilities	35,069,605	31,545,816	29,294,856
Shareholders’ Equity
Non-cumulative preferred shares	830,000	830,000
Common shares ($0.0011 par, shares issued: 588,250,762 and 583,289,850)	654	648
Additional paid-in capital	2,211,444	2,085,075
Retained earnings	15,892,065	14,455,868
Accumulated other comprehensive income (loss), net of deferred income tax	(1,646,170)	(64,600)	488,895	$ 212,091
Common shares held in treasury, at cost (shares: 217,904,765 and 204,365,956)	(4,377,920)	(3,761,095)
Total shareholders' equity	12,910,073	13,545,896	$ 13,105,886
Total liabilities and shareholders' equity	$ 47,990,507	$ 45,100,945
Parenthetical information:
Common shares, par value per share	$ 0.0011	$ 0.0011
Common shares issued (shares)	588,250,762	583,289,850	579,000,841	574,617,195
Common shares held in treasury (shares)	217,904,765	204,365,956	172,280,199
Parent Company
Assets
Total investments	$ 7,282	$ 2,038
Cash	11,393	16,317
Investment in subsidiaries	14,191,188	14,822,024
Investment in operating affiliates	5,259	6,877
Due from Affiliates	1,554	11
Other assets	17,203	9,604
Total assets	14,233,879	14,856,871
Liabilities
Senior notes	1,286,567	1,286,208
Other liabilities	37,239	24,767
Total liabilities	1,323,806	1,310,975
Shareholders’ Equity
Non-cumulative preferred shares	830,000	830,000
Common shares ($0.0011 par, shares issued: 588,250,762 and 583,289,850)	654	648
Additional paid-in capital	2,211,444	2,085,075
Retained earnings	15,892,065	14,455,868
Accumulated other comprehensive income (loss), net of deferred income tax	(1,646,170)	(64,600)
Common shares held in treasury, at cost (shares: 217,904,765 and 204,365,956)	(4,377,920)	(3,761,095)
Total shareholders' equity	12,910,073	13,545,896
Total liabilities and shareholders' equity	$ 14,233,879	$ 14,856,871
Parenthetical information:
Common shares, par value per share	$ 0.0011	$ 0.0011
Common shares issued (shares)	588,250,762	583,289,850
Common shares held in treasury (shares)	217,904,765	204,365,956