NSTS Bancorp, Inc. Quarterly report pursuant to Section 13 or 15(d)

Note 7 - Fair Value Measurements - Fair Value On Recurring Basis (Details)

Note 7 - Fair Value Measurements - Fair Value On Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Securities available for sale	$ 109,526	$ 121,205
U.S. Treasury Notes [Member]
Securities available for sale	5,866	7,288
US Government Agencies Debt Securities [Member]
Securities available for sale	19,848	21,390
Municipal Bonds [Member]
Securities available for sale	18,138	19,637
Residential Mortgage-Backed Securities [Member]
Securities available for sale	30,959	35,738
Fair Value, Recurring [Member]
Securities available for sale	109,526	121,205
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	5,866	7,288
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	103,660	113,917
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| U.S. Treasury Notes [Member]
Securities available for sale	5,866	7,288
Fair Value, Recurring [Member] \| U.S. Treasury Notes [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	5,866	7,288
Fair Value, Recurring [Member] \| U.S. Treasury Notes [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| U.S. Treasury Notes [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Securities available for sale	19,848	21,390
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	19,848	21,390
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Municipal Bonds [Member]
Securities available for sale	18,138	19,637
Fair Value, Recurring [Member] \| Municipal Bonds [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Municipal Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	18,138	19,637
Fair Value, Recurring [Member] \| Municipal Bonds [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Residential Mortgage-Backed Securities [Member]
Securities available for sale	30,959	35,738
Fair Value, Recurring [Member] \| Residential Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Residential Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	30,959	35,738
Fair Value, Recurring [Member] \| Residential Mortgage-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member]
Securities available for sale	34,715	37,152
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale	34,715	37,152
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale	$ 0	$ 0