Regulatory Capital (Tables)

12 Months Ended

Dec. 31, 2017

Banking and Thrift [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, 2017 and 2016 are presented in the following tables:

	Actual				Adequately Capitalized  Basel III Phase-In Schedule				Adequately Capitalized Basel III Fully Phased-In				Well Capitalized (1)
	Amount		Ratio		Amount		Ratio		Amount		Ratio		Amount		Ratio
December 31, 2017
Total risk-based capital:
Consolidated	$	1,112.5	12.76	%	$	806.5	9.25	%	$	915.5	10.50	%	$	871.9	10.00	%
FIB	1,066.6		12.29		802.7		9.25		911.2		10.50		867.8		10.00
Tier 1 risk-based capital:
Consolidated	1,040.3		11.93		632.1		7.25		741.1		8.50		697.5		8.00
FIB	994.4		11.46		629.1		7.25		737.6		8.50		694.2		8.00
Common equity tier 1 risk-based capital:
Consolidated	962.4		11.04		501.3		5.75		610.3		7.00		566.7		6.50
FIB	994.4		11.46		499.0		5.75		607.4		7.00		564.1		6.50
Leverage capital ratio:
Consolidated	1,040.3		8.86		469.9		4.00		469.9		4.00		587.4		5.00
FIB	994.4		8.48		469.1		4.00		469.1		4.00		586.3		5.00

	Actual				Adequately Capitalized  Basel III Phase-In Schedule				Adequately Capitalized Basel III Fully Phased-In				Well Capitalized (1)
	Amount		Ratio		Amount		Ratio		Amount		Ratio		Amount		Ratio
December 31, 2016
Total risk-based capital:
Consolidated	$	974.5	15.13	%	$	555.7	8.63	%	$	676.1	10.50	%	$	643.9	10.00	%
FIB	842.0		13.13		553.5		8.63		673.4		10.50		641.3		10.00
Tier 1 risk-based capital:
Consolidated	894.3		13.89		426.9		6.63		547.3		8.50		515.1		8.00
FIB	765.8		11.94		425.2		6.63		545.1		8.50		513.1		8.00
Common equity tier 1 risk-based capital:
Consolidated	814.3		12.65		330.3		5.13		450.7		7.00		418.5		6.50
FIB	765.8		11.94		329.0		5.13		448.9		7.00		416.9		6.50
Leverage capital ratio:
Consolidated	894.3		10.11		353.8		4.00		353.8		4.00		442.3		5.00
FIB	765.8		8.69		352.3		4.00		352.3		4.00		440.4		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.