Parent Company - Condensed Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income
Total revenue	$ 836,942	$ 793,074	$ 715,475
Noninterest expense
Salaries and employee benefits	225,755	199,129	182,384
Contracted services and professional fees	66,423	70,027	63,349
Equipment	45,109	34,506	24,719
Other	62,928	57,186	66,082
Total noninterest expense	501,138	440,471	405,479
Provision (Benefit) for income taxes	(74,191)	(85,526)	(83,261)
Net income	234,983	265,685	265,735
Comprehensive income (loss)	344,027	(251,876)	112,438
First Hawaiian, Inc.
Income
Dividends from FHB	139,500	157,000	213,500
Other income	2,492
Total revenue	141,992	157,000	213,500
Noninterest expense
Salaries and employee benefits	4,404	4,098	3,732
Contracted services and professional fees	3,554	6,200	2,731
Equipment	102	78
Other	1,474	1,447	1,314
Total noninterest expense	9,534	11,823	7,777
Income before benefit for income taxes and equity in undistributed income of FHB	132,458	145,177	205,723
Provision (Benefit) for income taxes	145	(2,707)	(1,877)
Equity in undistributed income of FHB	$ 102,670	$ 117,801	$ 58,135