Derivatives and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Offsetting Assets

The following table illustrates the potential effect of the Company's master netting arrangements, by type of financial instrument, on the Company's consolidated balance sheets as of December 31, 2017 and December 31, 2016:

	December 31, 2017
	Gross Amounts Recognized		Gross Amounts Offset in the Balance Sheet		Net Amounts in the Balance Sheet		Financial Instruments		Fair Value of Financial Collateral in the Balance Sheet		Net Amount
Financial Assets
Interest rate swap contracts	$	7.5	$	—	$	7.5	$	2.4	$	—	$	5.1
Mortgage related derivatives	1.3		—		1.3		—		—		1.3
Total derivatives	8.8		—		8.8		2.4		—		6.4
Total assets	$	8.8	$	—	$	8.8	$	2.4	$	—	$	6.4
Financial Liabilities
Interest rate swap contracts	$	7.8	$	—	$	7.8	$	2.4	$	3.3	$	2.1
Mortgage related derivatives	0.1		—		0.1		—		—		0.1
Total derivatives	7.9		—		7.9		2.4		3.3		2.2
Repurchase agreements	643.0		—		643.0		—		643.0		—
Total liabilities	$	650.9	$	—	$	650.9	$	2.4	$	646.3	$	2.2

	December 31, 2016
	Gross Amounts Recognized		Gross Amounts Offset in the Balance Sheet		Net Amounts in the Balance Sheet		Financial Instruments		Fair Value of Financial Collateral in the Balance Sheet		Net Amount
Financial Assets
Interest rate swap contracts	$	1.3	$	—	$	1.3	$	0.5	$	—	$	0.8
Mortgage related derivatives	1.4		—		1.4		—		—		1.4
Total derivatives	2.7		—		2.7		0.5		—		2.2
Total assets	$	2.7	$	—	$	2.7	$	0.5	$	—	$	2.2
Financial Liabilities
Interest rate swap contracts	$	1.3	$	—	$	1.3	$	0.5	$	—	$	0.8
Total derivatives	1.3		—		1.3		0.5		—		0.8
Repurchase agreements	537.6		—		537.6		—		537.6		—
Total liabilities	$	538.9	$	—	$	538.9	$	0.5	$	537.6	$	0.8

Offsetting Liabilities

The following table illustrates the potential effect of the Company's master netting arrangements, by type of financial instrument, on the Company's consolidated balance sheets as of December 31, 2017 and December 31, 2016:

	December 31, 2017
	Gross Amounts Recognized		Gross Amounts Offset in the Balance Sheet		Net Amounts in the Balance Sheet		Financial Instruments		Fair Value of Financial Collateral in the Balance Sheet		Net Amount
Financial Assets
Interest rate swap contracts	$	7.5	$	—	$	7.5	$	2.4	$	—	$	5.1
Mortgage related derivatives	1.3		—		1.3		—		—		1.3
Total derivatives	8.8		—		8.8		2.4		—		6.4
Total assets	$	8.8	$	—	$	8.8	$	2.4	$	—	$	6.4
Financial Liabilities
Interest rate swap contracts	$	7.8	$	—	$	7.8	$	2.4	$	3.3	$	2.1
Mortgage related derivatives	0.1		—		0.1		—		—		0.1
Total derivatives	7.9		—		7.9		2.4		3.3		2.2
Repurchase agreements	643.0		—		643.0		—		643.0		—
Total liabilities	$	650.9	$	—	$	650.9	$	2.4	$	646.3	$	2.2

	December 31, 2016
	Gross Amounts Recognized		Gross Amounts Offset in the Balance Sheet		Net Amounts in the Balance Sheet		Financial Instruments		Fair Value of Financial Collateral in the Balance Sheet		Net Amount
Financial Assets
Interest rate swap contracts	$	1.3	$	—	$	1.3	$	0.5	$	—	$	0.8
Mortgage related derivatives	1.4		—		1.4		—		—		1.4
Total derivatives	2.7		—		2.7		0.5		—		2.2
Total assets	$	2.7	$	—	$	2.7	$	0.5	$	—	$	2.2
Financial Liabilities
Interest rate swap contracts	$	1.3	$	—	$	1.3	$	0.5	$	—	$	0.8
Total derivatives	1.3		—		1.3		0.5		—		0.8
Repurchase agreements	537.6		—		537.6		—		537.6		—
Total liabilities	$	538.9	$	—	$	538.9	$	0.5	$	537.6	$	0.8

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value

The notional amounts and estimated fair values of the Company's derivatives are presented in the following table. Fair value estimates are obtained from third parties and are based on pricing models.

	December 31, 2017				December 31, 2016
	Notional Amount		Estimated Fair Value		Notional Amount		Estimated Fair Value
Derivative Assets (included in other assets on the consolidated balance sheets)
Non-hedging interest rate derivatives:
Interest rate swap contracts	$	344.2	$	7.5	$	53.6	$	1.3
Interest rate lock commitments	60.7		1.3		73.4		1.1
Forward loan sales contracts	—		—		126.8		0.3
Total derivative assets	$	404.9	$	8.8	$	253.8	$	2.7
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets)
Derivatives designated as hedges:
Interest rate swap contracts	$	—	$	—	$	100.0	$	—
Non-hedging interest rate derivatives:
Interest rate swap contracts	344.2		7.8		53.6		1.3
Forward loan sales contracts	88.8		0.1		—		—
Total derivative liabilities	$	433.0	$	7.9	$	153.6	$	1.3

Derivative Instruments, Gain (Loss)

The following table presents the pre-tax gains or losses related to derivative contracts that were recorded in accumulated other comprehensive income and other non-interest income in the Company's statements of income:

As of or For The Year Ended December 31,	2017			2016			2015
Derivatives designated as hedges:
Amount of loss recognized in other comprehensive income (effective portion)	$	(1.1	)	$	(0.2	)	$	0.2
Reclassification adjustment for derivative net (gains) losses included in income	1.1			—			—
Non-hedging interest rate derivatives:
Amount of gain (loss) recognized in other non-interest income	—			0.1			—
Amount of net fee income recognized in other non-interest income	0.8			0.9			0.1
Amount of net gains (losses) recognized in mortgage banking revenues	(1.7		)	1.4			—