Schedule I - Condensed Financial Information of Registrant - CONDENSED STATEMENTS OF CASH FLOWS, PARENT COMPANY (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash Flows from Operating Activities
Net Cash Provided by Operating Activities	$ 452,731	$ 404,499	$ 389,309
Cash Flows from Investing Activities
Investment in Subsidiaries	(61,573)	(8,378)	(8,283)
Net Cash Used in Investing Activities	(411,374)	(289,287)	(175,071)
Cash Flows from Financing Activities
Net (Repayments) Borrowings on Short-Term Debt	(11,807)	73,218	(82,959)
Payments for Shares Withheld for Employee Tax Obligations	(6,457)	(3,088)	(2,942)
Dividends Paid	(78,266)	(73,061)	(68,755)
Other, net	(549)	(904)	(2,123)
Net Cash Provided by (Used in) Financing Activities	22,921	(3,835)	(96,779)
Net Change in Cash and Cash Equivalents	64,278	111,377	117,459
Cash and Cash Equivalents at Beginning of Period	230,373	118,996	1,537
Cash and Cash Equivalents at End of Period	294,651	230,373	118,996
OTC
Cash Flows from Operating Activities
Net Cash Provided by Operating Activities	76,333	77,139	28,807
Cash Flows from Investing Activities
Other, net	1,394	1,686	1,480
Net Cash Used in Investing Activities	(106,691)	(40,068)	(51,695)
Cash Flows from Financing Activities
Net (Repayments) Borrowings on Short-Term Debt	0	0	(22,637)
Borrowings from Subsidiaries	179,247	148,308	236,926
Payments for Shares Withheld for Employee Tax Obligations	(6,457)	(3,088)	(2,942)
Dividends Paid	(78,265)	(73,061)	(68,755)
Other, net	(729)	(339)	(461)
Net Cash Provided by (Used in) Financing Activities	93,796	71,820	142,131
Net Change in Cash and Cash Equivalents	63,438	108,891	119,243
Cash and Cash Equivalents at Beginning of Period	228,137	119,246	3
Cash and Cash Equivalents at End of Period	291,575	228,137	119,246
OTC \| Subsidiaries
Cash Flows from Investing Activities
Investment in Subsidiaries	(55,000)	(40,000)	(50,000)
Purchases of Investments and Other Assets	$ (53,085)	$ (1,754)	$ (3,175)

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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