Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Jun. 01, 2022 USD ($) $ / shares shares	Jun. 01, 2021 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) director $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 3,000	$ 2,300	$ 2,500
Income tax benefits related to stock-based compensation expense			$ 700	$ 500	$ 600
Non-Employee Director Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of directors | director			12
Director equity grants granted, value			$ 32
Granted during the period (in shares) | shares	10,344	7,050
Granted during the period, per director (in shares) | shares	862	705
Granted during the period (in usd per share) | $ / shares	$ 37.12	$ 45.41
Director equity grants. expense	$ 384	$ 320
Long-Term Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted during the period (in shares) | shares			95,960	104,414	68,704
Granted during the period (in usd per share) | $ / shares			$ 38.09	$ 40.56	$ 26.96
Unrecognized compensation expense			$ 4,700
Unrecognized compensation expense, period for recognition			2 years 1 month 6 days
Long-Term Restricted Stock | Next Twelve Months
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense			$ 2,500
First Bancorp 2014 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares remaining available for grant (in shares) | shares			348,087