Regulatory Matters - Summary of Capital Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Common Equity Tier 1 Capital:
Minimum, Percent	4.50%
Tier 1 Capital:
Minimum, Percent	6.00%
Tier 1 Capital Leverage Ratio:
Minimum, Percent	4.00%
Fidelity Bank
Common Equity Tier 1 Capital:
Actual	$ 355,580	$ 337,337
Minimum	$ 182,245	$ 176,925
Actual, Percent	8.78%	8.58%
Minimum, Percent	4.50%	4.50%
Tier 1 Capital:
Actual	$ 371,407	$ 352,601
Minimum	$ 243,014	$ 235,854
Actual, Percent	9.17%	8.97%
Minimum, Percent	6.00%	6.00%
Total Risk-Based Capital:
Actual	$ 487,149	$ 468,234
Minimum	$ 323,956	$ 314,515
Actual, Percent	12.03%	11.91%
Minimum, Percent	8.00%	8.00%
Tier 1 Capital Leverage Ratio:
Actual, Percent	8.34%	8.14%
Minimum, Percent	4.00%	4.00%
Fidelity Southern Corporation
Common Equity Tier 1 Capital:
Actual	$ 349,133	$ 328,193
Minimum	$ 177,225	$ 176,870
Actual, Percent	8.86%	8.35%
Minimum, Percent	4.50%	4.50%
Tier 1 Capital:
Actual	$ 393,818	$ 371,841
Minimum	$ 236,291	$ 235,840
Actual, Percent	10.00%	9.46%
Minimum, Percent	6.00%	6.00%
Total Risk-Based Capital:
Actual	$ 498,166	$ 476,081
Minimum	$ 315,071	$ 314,504
Actual, Percent	12.65%	12.11%
Minimum, Percent	8.00%	8.00%
Tier 1 Capital Leverage Ratio:
Actual, Percent	8.85%	8.58%
Minimum, Percent	4.00%	4.00%

Common Equity Tier One Capital, Risk Based Capital

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The amount of total capital as defined in the regulations.

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