Capital Requirements and Regulatory Restrictions (Tables)

12 Months Ended

Dec. 31, 2022

Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]

Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations

The Company’s and the Bank’s actual and required capital amounts and ratios are as follows:

	Actual				Capital Requirements				Requirement to be Well-Capitalized
(In thousands)	Amount		Ratio		Amount		Ratio		Amount	Ratio
At December 31, 2022
Total capital (to risk-weighted assets)
Cass Information Systems, Inc.	$	257,313	13.52	%	$	152,306	8.00	%	$        N/A	N/A %
Cass Commercial Bank	186,075		16.00		93,044		8.00		116,305	10.00
Common Equity Tier I Capital (to risk-weighted assets)
Cass Information Systems, Inc.	243,774		12.80		85,672		4.50		N/A	N/A
Cass Commercial Bank	172,848		14.86		52,337		4.50		75,598	6.50
Tier I capital (to risk-weighted assets)
Cass Information Systems, Inc.	243,774		12.80		114,229		6.00		N/A	N/A
Cass Commercial Bank	172,848		14.86		69,783		6.00		93,044	8.00
Tier I capital (to average assets)
Cass Information Systems, Inc.	243,774		9.52		102,386		4.00		N/A	N/A
Cass Commercial Bank	172,848		10.77		64,196		4.00		80,245	5.00
At December 31, 2021
Total capital (to risk-weighted assets)
Cass Information Systems, Inc.	$	240,265	14.86	%	$	129,339	8.00	%	$        N/A	N/A %
Cass Commercial Bank	174,614		17.21		81,163		8.00		101,454	10.00
Common Equity Tier I Capital (to risk-weighted assets)
Cass Information Systems, Inc.	228,224		14.11		72,764		4.50		N/A	N/A
Cass Commercial Bank	163,030		16.07		45,654		4.50		65,945	6.50
Tier I capital (to risk-weighted assets)
Cass Information Systems, Inc.	228,224		14.11		97,019		6.00		N/A	N/A
Cass Commercial Bank	163,030		16.07		60,872		6.00		81,163	8.00
Tier I capital (to average assets)
Cass Information Systems, Inc.	228,224		9.21		99,163		4.00		N/A	N/A
Cass Commercial Bank	163,030		11.05		59,036		4.00		73,795	5.00