FIRST BANCORP. (Holding Company Only) Financial Information - Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income:
Interest income on money market investments	$ 24,122	$ 27,110
Expense:
Income tax expense	23,955	31,935
Net income	73,458	70,698
Other comprehensive (loss) income, net of tax	(15,065)	87,228
Comprehensive income (loss)	58,393	157,926
Holding Company [Member]
Income:
Interest income on money market investments	63	53
Dividend income	80,917	78,870
Other income	101	102
Total income	81,081	79,025
Expense:
Interest expense on long-term borrowings	3,350	3,381
Other non-interest expenses	439	410
Total expenses	3,789	3,791
Income before income taxes and equity in undistributed earnings of subsidiaries	77,292	75,234
Income tax expense	1	1
Equity in undistributed earnings of subsidiaries (distributions in excess of earnings)	(3,833)	(4,535)
Net income	73,458	70,698
Other comprehensive (loss) income, net of tax	(15,065)	87,228
Comprehensive income (loss)	$ 58,393	$ 157,926