Regulatory Capital (Tables)

12 Months Ended

Dec. 31, 2021

Banking Regulation, Risk-Based Information [Abstract]

Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations

The Company’s actual capital amounts and ratios and selected minimum regulatory thresholds and prompt corrective action provisions as of December 31, 2021 and 2020 are presented in the following tables:

	Actual			Minimum Required for Capital Adequacy Purposes				For Capital Adequacy Purposes Plus Capital Conservation Buffer				Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements (1)
December 31, 2021	Amount		Ratio	Amount		Ratio		Amount		Ratio		Amount		Ratio
Total risk-based capital:
Consolidated	$	1,659.3	14.11	$	940.9	8.00	%	$	1,235.0	10.50	%	$	1,176.2	10.00	%
FIB	1,472.5		12.56	938.0		8.00		1,231.1		10.50		1,172.5		10.00
Tier 1 risk-based capital:
Consolidated	1,469.0		12.49	705.7		6.00		999.7		8.50		940.9		8.00
FIB	1,382.2		11.79	703.5		6.00		996.6		8.50		938.0		8.00
Common equity tier 1 risk-based capital:
Consolidated	1,384.8		11.77	529.3		4.50		823.3		7.00		764.5		6.50
FIB	1,382.2		11.79	527.6		4.50		820.8		7.00		762.1		6.50
Leverage capital ratio:
Consolidated	1,469.0		7.68	765.5		4.00		765.5		4.00		956.9		5.00
FIB	1,382.2		7.24	764.1		4.00		764.1		4.00		955.1		5.00

	Actual				Minimum Required for Capital Adequacy Purposes				For Capital Adequacy Purposes Plus Capital Conservation Buffer				Minimum to Be Well Capitalized Under Prompt Corrective Action Requirements (1)
December 31, 2020	Amount		Ratio		Amount		Ratio		Amount		Ratio		Amount		Ratio
Total risk-based capital:
Consolidated	$	1,575.7	14.19	%	$	888.3	8.00	%	$	1,165.8	10.50	%	$	1,110.3	10.00	%
FIB	1,426.8		12.89		885.6		8.00		1,162.3		10.50		1,107.0		10.00
Tier 1 risk-based capital:
Consolidated	1,369.0		12.33		666.2		6.00		943.8		8.50		888.3		8.00
FIB	1,320.1		11.93		664.2		6.00		940.9		8.50		885.6		8.00
Common equity tier 1 risk-based capital:
Consolidated	1,284.9		11.57		499.6		4.50		777.2		7.00		721.7		6.50
FIB	1,320.1		11.93		498.1		4.50		774.9		7.00		719.5		6.50
Leverage capital ratio:
Consolidated	1,369.0		8.16		671.0		4.00		671.0		4.00		838.7		5.00
FIB	1,320.1		7.88		669.7		4.00		669.7		4.00		837.2		5.00

(1) The ratios for the well capitalized requirement are only applicable to FIB. However, the Company manages its capital position as if the requirement applies to the consolidated entity and has presented the ratios as if they also applied on a consolidated basis.