Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis

Financial assets and financial liabilities measured at fair value on a recurring basis are as follows:

			Fair Value Measurements at Reporting Date Using
As of December 31, 2019	Balance		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investment debt securities available-for-sale:
U.S. Treasury Notes	$	9.0	$	—	$	9.0	$	—
State, county and municipal securities	80.9		—		80.9		—
Obligations of U.S. government agencies	366.8		—		366.8		—
U.S. agency mortgage-backed securities & collateralized mortgage obligations	2,317.2		—		2,317.2		—
Private mortgage-backed securities	47.2		—		47.2		—
Corporate securities	135.7		—		135.7		—
Other investments	3.2		—		3.2		—
Loans held for sale	100.9		—		100.9		—
Derivative assets:
Interest rate swap contracts	21.9		—		21.9		—
Interest rate lock commitments	1.3		—		1.3		—
Derivative liabilities:
Interest rate swap contracts	21.9		—		21.9		—
Forward loan sales contracts	0.3		—		0.3		—
Deferred compensation plan assets	18.2		—		18.2		—
Deferred compensation plan liabilities	18.2		—		18.2		—

			Fair Value Measurements at Reporting Date Using
As of December 31, 2018	Balance		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investment debt securities available-for-sale:
U.S. Treasury Notes	$	2.6	$	—	$	2.6	$	—
Obligations of U.S. government agencies	559.2		—		559.2		—
U.S. agency mortgage-backed securities & collateralized mortgage obligations	1,544.8		—		1,544.8		—
Private mortgage-backed securities	70.2		—		70.2		—
Corporate securities	91.9		—		91.9		—
Other investments	2.0		—		2.0		—
Loans held for sale	33.3		—		33.3		—
Derivative assets:
Interest rate swap contracts	8.8		—		8.8		—
Interest rate lock commitments	1.3		—		1.3		—
Derivative liabilities:
Interest rate swap contracts	8.8		—		8.8		—
Forward loan sales contracts	0.6		—		0.6		—
Deferred compensation plan assets	12.1		—		12.1		—
Deferred compensation plan liabilities	12.1		—		12.1		—

Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Non-Recurring Basis

The following table presents information about the Company’s assets and liabilities measured at fair value on a non-recurring basis:

			Fair Value Measurements at Reporting Date Using
As of December 31, 2019	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs  (Level 2)		Significant Unobservable Inputs (Level 3)		Total Gains (Losses)
Impaired loans	$	27.6	$	—	$	—	$	27.6	$	(13.7	)
Other real estate owned	2.2		—		—		2.2		(1.2		)
Long-lived assets to be disposed of by sale	6.2		—		—		6.2		(0.2		)

			Fair Value Measurements at Reporting Date Using
As of December 31, 2018	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Gains (Losses)
Impaired loans	$	24.1	$	—	$	—	$	24.1	$	(12.2	)
Other real estate owned	0.6		—		—		0.6		(0.6		)
Long-lived assets to be disposed of by sale	4.9		—		—		4.9		(0.5		)

Fair Value Inputs, Assets, Quantitative Information

The following table presents additional quantitative information about assets measured at fair value on a non-recurring basis and for which the Company has utilized Level 3 inputs to determine fair values:

As of December 31, 2019	Fair Value		Valuation Technique	Unobservable Inputs	Range (Weighted Average)
Impaired loans	$	27.6	Appraisal	Appraisal adjustment	0%	-	56%	(22%)
Other real estate owned	2.2		Appraisal	Appraisal adjustment	8%	-	65%	(27%)
Long-lived assets to be disposed of by sale	6.2		Appraisal	Appraisal adjustment	0%	-	37%	(3%)
As of December 31, 2018	Fair Value		Valuation Technique	Unobservable Inputs	Range (Weighted Average)
Impaired loans	$	24.1	Appraisal	Appraisal adjustment	0%	-	26%	(13%)
Other real estate owned	0.6		Appraisal	Appraisal adjustment	8%	-	96%	(39%)
Long-lived assets to be disposed of by sale	4.9		Appraisal	Appraisal adjustment	0%	-	43%	(10%)

Fair Value, by Balance Sheet Grouping

The estimated fair values of financial instruments that are reported in the Company’s consolidated balance sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, are as follows:

	`				Fair Value Measurements at Reporting Date Using
As of December 31, 2019	Carrying Amount		Estimated Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	$	1,076.8	$	1,076.8	$	1,076.8	$	—	$	—
Investment debt securities available-for-sale	2,960.0		2,960.0		—		2,960.0		—
Investment debt securities held-to-maturity	92.3		94.5		—		94.5		—
Accrued interest receivable	46.7		46.7		—		46.7		—
Mortgage servicing rights, net	30.2		34.8		—		34.8		—
Loans held for sale	100.9		100.9		—		100.9		—
Net loans held for investment	8,857.7		8,930.7		—		8,906.7		24.0
Derivative assets	23.2		23.2		—		23.2		—
Deferred compensation plan assets	18.2		18.2		—		18.2		—
Total financial assets	$	13,206.0	$	13,285.8	$	1,076.8	$	12,185.0	$	24.0
Financial liabilities:
Total deposits, excluding time deposits	$	10,213.5	$	10,213.5	$	10,213.5	$	—	$	—
Time deposits	1,450.0		1,446.6		—		1,446.6		—
Securities sold under repurchase agreements	697.6		697.6		—		697.6		—
Accrued interest payable	12.1		12.1		—		12.1		—
Long-term debt	13.9		10.4		—		10.4		—
Subordinated debentures held by subsidiary trusts	86.9		81.3		—		81.3		—
Derivative liabilities	22.2		22.2		—		22.2		—
Deferred compensation plan liabilities	18.2		18.2		—		18.2		—
Total financial liabilities	$	12,514.4	$	12,501.9	$	10,213.5	$	2,288.4	$	—

					Fair Value Measurements at Reporting Date Using
As of December 31, 2018	Carrying Amount		Estimated Fair Value		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	$	822.0	$	822.0	$	822.0	$	—	$	—
Investment debt securities available-for-sale	2,270.7		2,270.7		—		2,270.7		—
Investment debt securities held-to-maturity	406.8		400.7		—		400.7		—
Accrued interest receivable	44.9		44.9		—		44.9		—
Mortgage servicing rights, net	27.7		42.4		—		42.4		—
Loans held for sale	33.3		33.3		—		33.3		—
Net loans held for investment	8,397.4		8,439.7		—		8,415.6		24.1
Derivative assets	10.1		10.1		—		10.1		—
Deferred compensation plan assets	12.1		12.1		—		12.1		—
Total financial assets	$	12,025.0	$	12,075.9	$	822.0	$	11,229.8	$	24.1
Financial liabilities:
Total deposits, excluding time deposits	$	9,363.7	$	9,363.7	$	9,363.7	$	—	$	—
Time deposits	1,317.0		1,299.0		—		1,299.0		—
Securities sold under repurchase agreements	712.4		712.4		—		712.4		—
Accrued interest payable	7.8		7.8		—		7.8		—
Long-term debt	15.8		13.0		—		13.0		—
Subordinated debentures held by subsidiary trusts	86.9		84.9		—		84.9		—
Derivative liabilities	9.4		9.4		—		9.4		—
Deferred compensation plan liabilities	12.1		12.1		—		12.1		—
Total financial liabilities	$	11,525.1	$	11,502.3	$	9,363.7	$	2,138.6	$	—