FIRST BANCORP. (Holding Company Only) Financial Information - Statements of Financial Condition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
ASSETS
Cash and due from banks	$ 1,158,215	$ 661,925	$ 478,480
Other assets	276,754	229,215
Total assets	19,292,921	18,909,549
Liabilities:
Long-term borrowings	61,700	161,700
Accounts payable and other liabilities	190,687	194,255
Liabilities	17,623,685	17,411,940
Stockholders Equity	1,669,236	1,497,609	$ 1,325,540
Total liabilities and stockholders' equity	19,292,921	18,909,549
Holding Company [Member]
ASSETS
Cash and due from banks	13,295	11,452
Other investment securities	1,275	825
Dividends receivable	619	713
Other assets	459	476
Total assets	1,735,619	1,663,864
Liabilities:
Long-term borrowings	61,700	161,700
Accounts payable and other liabilities	4,683	4,555
Liabilities	66,383	166,255
Stockholders Equity	1,669,236	1,497,609
Total liabilities and stockholders' equity	1,735,619	1,663,864
Holding Company [Member] | Investment In Banking Subsidiary [Member]
ASSETS
Investments	1,694,000	1,627,172
Holding Company [Member] | Non Banking Subsidiary [Member]
ASSETS
Investments	24,121	18,376
Holding Company [Member] | Statutory Trust One [Member]
ASSETS
Investments	1,289	1,289
Holding Company [Member] | Statutory Trust Two [Member]
ASSETS
Investments	561	$ 3,561
Holding Company [Member] | Statutory Trust Two [Member] | Trust Preferred Securities [Member]
Liabilities:
Trust preferred securities repurchased	$ 97,000
Trust preferred purchase price percent	84.00%
Interest in Trust Preferred Securities	$ 3,000
Repurchased face amount	$ 100,000