BASIS OF PRESENTATION (Narrative) (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Apr. 27, 2024 $ / shares	Mar. 31, 2024 USD ($) segment $ / shares	Apr. 28, 2024 $ / shares shares	Dec. 31, 2023 USD ($) $ / shares
Business Acquisition [Line Items]
Common stock, par value (in dollars per share) | $ / shares		$ 1		$ 1
Number of operating segments | segment		1
Qualified Affordable Housing Investments
Affordable housing project investments		$ 5,700		$ 5,900
Affordable housing tax credits, amount		257
Affordable housing, other tax benefits, amount		33
Affordable housing tax credits and other tax benefits, amount		290
Affordable housing project investments, amortization		235
Income (loss) from affordable housing projects		$ 55
Subsequent Event | Bank Merger
Business Acquisition [Line Items]
Common stock, par value (in dollars per share) | $ / shares			$ 1.00
Business combination, equity interest conversion per common share (in shares) | shares			0.55
Business combination, equity interest conversion, per preferred share (in shares) | shares			1
Subsequent Event | Bank Merger | HTLF
Business Acquisition [Line Items]
Common stock, par value (in dollars per share) | $ / shares	$ 1.00
Preferred stock, percentage	7.00%
Preferred stock, par value (in dollars per share) | $ / shares	$ 1.00