Accounting Pronouncements (Consolidated Balance Sheet Before After Transition Date (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Statements Adjusted [Abstract]
Deferred policy acquisition costs, net	$ 123,015	$ 121,224
Assets	20,330,165	19,058,758	$ 19,002,576
Policy benefits and losses, claims and loss expenses payable	829,992	849,113
Deferred Income Tax Liabilities, Net	1,507,604	1,447,125
Total liabilities	12,698,832	11,886,313
Accumulated other comprehensive loss	187,238	223,216
Retained earnings	8,023,000	7,600,090
Stockholders' Equity Attributable to Parent	7,631,333	7,172,445
Liabilities and Equity	$ 20,330,165	$ 19,058,758