Condensed Financial Statements of Unity Bancorp, Inc. (Parent Company Only) - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 114,793	$ 244,818
Estimated fair value	9,793	8,566
Premises and equipment, net	20,002	19,914
Total assets	2,444,948	2,033,713
LIABILITIES AND SHAREHOLDERS' EQUITY
Subordinated debentures	10,310	10,310
Shareholders' equity	239,227	205,729	$ 173,911	$ 160,709
Total liabilities and shareholders' equity	2,444,948	2,033,713
Parent Company Only | Reportable Legal Entities
ASSETS
Cash and cash equivalents	2,225	1,685
Estimated fair value	5,697	5,043
Investment in subsidiaries	239,255	207,799
Premises and equipment, net	3,594	3,709
Other assets	972
Total assets	251,743	218,236
LIABILITIES AND SHAREHOLDERS' EQUITY
Loan due to subsidiary bank	2,002	2,108
Other liabilities	204	89
Subordinated debentures	10,310	10,310
Shareholders' equity	239,227	205,729
Total liabilities and shareholders' equity	$ 251,743	$ 218,236