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Schedule I - Condensed Financial Information of Registrant - CONDENSED STATEMENTS OF CASH FLOWS, PARENT COMPANY (Details) - USD ($) $ in Thousands | 12 Months Ended
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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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