Regulatory Matters (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
PCB Bancorp
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital conservation buffer	8.86%	8.90%
Actual
Common tier 1 capital (to risk-weighted assets), amount	$ 226,728	$ 226,069
Common tier 1 capital (to risk-weighted assets), ratio	0.1560	0.1587
Total capital (to risk-weighted assets), amount	$ 244,978	$ 240,750
Total capital (to risk-weighted assets), ratio	0.1686	0.1690
Tier 1 capital (to risk-weighted assets), amount	$ 226,728	$ 226,069
Tier 1 capital (to risk-weighted assets), ratio	0.1560	0.1587
Tier 1 capital (to average assets), amount	$ 226,728	$ 226,069
Tier 1 capital (to average assets), ratio	0.1140	0.1323
Minimum Capital Requirement
Common tier 1 capital (to risk-weighted assets), amount	$ 65,404	$ 64,087
Common tier 1 capital (to risk-weighted assets), ratio	4.50%	4.50%
Total capital (to risk-weighted assets), amount	$ 116,274	$ 113,933
Total capital (to risk-weighted assets), ratio	0.080	0.080
Tier 1 capital (to risk-weighted assets), amount	$ 87,206	$ 85,450
Tier 1 capital (to risk-weighted assets), ratio	0.060	0.060
Tier 1 capital (to average assets), amount	$ 79,532	$ 68,355
Tier 1 capital (to average assets), ratio	0.040	0.040
Pacific City Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital conservation buffer	8.60%	8.71%
Actual
Common tier 1 capital (to risk-weighted assets), amount	$ 222,960	$ 223,241
Common tier 1 capital (to risk-weighted assets), ratio	0.1534	0.1568
Total capital (to risk-weighted assets), amount	$ 241,209	$ 237,922
Total capital (to risk-weighted assets), ratio	0.1660	0.1671
Tier 1 capital (to risk-weighted assets), amount	$ 222,960	$ 223,241
Tier 1 capital (to risk-weighted assets), ratio	0.1534	0.1568
Tier 1 capital (to average assets), amount	$ 222,960	$ 223,241
Tier 1 capital (to average assets), ratio	0.1121	0.1306
Minimum Capital Requirement
Common tier 1 capital (to risk-weighted assets), amount	$ 65,401	$ 64,084
Common tier 1 capital (to risk-weighted assets), ratio	4.50%	4.50%
Total capital (to risk-weighted assets), amount	$ 116,269	$ 113,928
Total capital (to risk-weighted assets), ratio	0.080	0.080
Tier 1 capital (to risk-weighted assets), amount	$ 87,202	$ 85,446
Tier 1 capital (to risk-weighted assets), ratio	0.060	0.060
Tier 1 capital (to average assets), amount	$ 79,529	$ 68,354
Tier 1 capital (to average assets), ratio	0.040	0.040
To Be Well Capitalized Under Prompt Corrective Provisions
Common tier 1 capital (to risk-weighted assets), amount	$ 94,468	$ 92,566
Common tier 1 capital (to risk-weighted assets), ratio	6.50%	6.50%
Total capital (to risk-weighted assets), amount	$ 145,336	$ 142,410
Total capital (to risk-weighted assets), ratio	0.100	0.100
Tier 1 capital (to risk-weighted assets), amount	$ 116,269	$ 113,928
Tier 1 capital (to risk-weighted assets), ratio	0.080	0.080
Tier 1 capital (to average assets), amount	$ 99,412	$ 85,442
Tier 1 capital (to average assets), ratio	0.050	0.050