Supplemental Executive Retirement Plan	12 Months Ended
Supplemental Executive Retirement Plan	Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]
Supplemental Executive Retirement Plan	Supplemental Executive Retirement Plan The Company sponsors a supplemental retirement plan for a select group of management or highly compensated employees of the Company under the 2005 Supplemental Executive Retirement Plan (the “SERP”). This plan was effective January 1, 2005, to replace the SERP originally effective January 1, 1993, which has been frozen. The SERP provides participating officers with the ability to defer income in addition to the benefits provided under the Company's Employee Thrift Plan. The SERP is a deferred compensation plan under which benefits are derived based on a notional account balance to be funded by the Company for each participating officer. The account balance was credited each year with a Company matching contribution of $20,000 or $35,000 based on the officer's plan. Plan participants could select from two investment options which included cash or stock units of the Company's stock. Assets of the SERP (i.e. the participants' account balances) were not physically invested in the investments selected by the participants; rather, they are utilized for the purpose of debiting or crediting additional amounts to each participants' account. The Company informally funded its obligation to plan participants in a rabbi trust, which is consolidated by the Company, and is comprised of a money market fund and Company stock reported at fair value based on quoted market prices. The assets held in the rabbi trust were reported at their estimated fair value of $10.7 million at December 31, 2024 and were included in cash and other assets in the Company's consolidated balance sheets. Effective December 3, 2024, the Company eliminated its common stock as an investment alternative available under Horizon’s 2005 Supplemental Executive Retirement Plan, as amended (the “Amended SERP”). As a result, the 203,440 shares of Horizon common stock beneficially owned under the SERP were liquidated. The amounts held in the rabbi trust were reported at their estimated fair value of $10.6 million at December 31, 2023 and were included in cash and stockholders' equity in the Company's consolidated balance sheets. The related accrued benefit cost (representing the Company's benefit obligation to participants) of $10.7 million and $10.6 million at December 31, 2024 and December 31, 2023, respectively, was recorded in other liabilities in the Company's consolidated balance sheets. The SERP is accounted for pursuant to FASB ASC section 710-10, “Compensation - Overall” (“ASC 710-10”). SERP participants are credited with a contribution to an account and will receive, upon separation, a benefit based upon the vested amount accrued in their account, which includes both the officer's and Company's contributions plus or minus the increase or decrease in the fair market value of the SERP assets selected by the participant. ASC 710-10 requires the Company to record a liability and related compensation expense during the service period. The Company is accruing the expense under the assumption that all participants in the SERP will achieve full vesting (five years of service). Following the vesting period, the liability continues to be remeasured each reporting period until extinguishment of the liability, with offsetting adjustments to compensation costs. The Company matching contribution and related expense was $433 thousand, $344 thousand and $404 thousand for the years ended December 31, 2024, December 31, 2023 and December 31, 2022, respectively.