Insider Trading Arrangements	3 Months Ended	6 Months Ended
Insider Trading Arrangements	Jun. 30, 2025 shares	Jun. 30, 2025 shares
Trading Arrangements, by Individual [Table]
Material Terms of Trading Arrangement [Text Block]		Item 5. OTHER INFORMATION. During the quarter ended June 30, 2025, no director or Section 16 officer adopted or terminated any Rule 10b5-1 trading arrangements or non-Rule 10b5-1 trading arrangements, as defined under Item 408(a) of Regulation S-K, except for Mr. Chang M. Liu, President and Chief Executive Officer of the Company, who entered into a Rule 10b5-1 trading agreement on May 1, 2025, with trading term ending on April 5, 2027. The trading plan provides for 20% of the vested net shares, after tax withholding, that are received by Mr. Liu as equity compensation during the term of the plan to be sold on future dates following the vesting dates of such equity awards. The trading plan also provides for 5,165 shares to be sold on or after October 28, 2025, which sale is intended to cover additional estimated tax liabilities associated with Performance RSU shares that vested on December 31, 2024 and were issued to him on April 1, 2025. The trading plan was adopted by Mr. Liu in order to generate cash to pay his estimated tax liabilities in connection with the vesting of such equity awards, which estimated tax liabilities are in excess of the value of the shares withheld.
Rule 10b5-1 Arrangement Adopted [Flag]	true
Trading Arrangement, Securities Aggregate Available Amount	5,165	5,165
Non-Rule 10b5-1 Arrangement Adopted [Flag]	false
Rule 10b5-1 Arrangement Terminated [Flag]	false
Non-Rule 10b5-1 Arrangement Terminated [Flag]	false
Trading Arrangement, Individual Name	Chang M. Liu
Trading Arrangement, Individual Title	President and Chief Executive Officer
Trading Arrangement Adoption Date	May 1, 2025
Trading Arrangement Expiration Date	April 5, 2027

CATHAY GENERAL BANCORP 10-Q