Other Comprehensive Income/Loss (Tables)

3 Months Ended

6 Months Ended

Mar. 31, 2021

Jun. 30, 2021

Equity [Abstract]

Schedule of Other Comprehensive Income and Related Tax Effects

The gross amounts of each component of other comprehensive income and the related tax effects are as follows:

	Pre-tax				Tax Expense (Benefit)				Net of Tax
Three Months Ended June 30,	2021		2020		2021		2020		2021		2020
Investment securities available-for sale:
Change in net unrealized (loss) gain during period	$	(0.8)	$	34.9	$	(0.2)	$	9.5	$	(0.6)	$	25.4
Reclassification adjustment for net loss included in net income	0.1		—		—		—		0.1		—
Net change in unamortized gains on available-for-sale securities transferred into held-to-maturity	24.8		—		6.3		—		18.5		—
Unrealized gain (loss) on derivatives	(0.8)		0.2		(0.2)		—		(0.6)		0.2
Defined benefits post-retirement benefit plan:
Change in net actuarial gains	—		(0.2)		—		—		—		(0.2)
Total other comprehensive (loss) income	$	23.3	$	34.9	$	5.9	$	9.5	$	17.4	$	25.4

	Pre-tax				Tax Expense (Benefit)				Net of Tax
Six Months Ended June 30,	2021		2020		2021		2020		2021		2020
Investment securities available-for sale:
Change in net unrealized (loss) gains during period	$	(67.6)	$	74.1	$	(17.2)	$	19.8	$	(50.4)	$	54.3
Reclassification adjustment for net loss included in net income	0.1		—		—		—		0.1		—
Net change in unamortized gains on available-for-sale securities transferred into held-to-maturity	24.8		—		6.3		—		18.5		—
Unrealized gain (loss) on derivatives	(0.9)		0.2		(0.2)		—		(0.7)		0.2
Defined benefits post-retirement benefit plan:
Change in net actuarial gains	—		(0.4)		—		(0.1)		—		(0.3)
Total other comprehensive income	$	(43.6)	$	73.9	$	(11.1)	$	19.7	$	(32.5)	$	54.2

Schedule of Accumulated Other Comprehensive Income (Loss)

The components of accumulated other comprehensive income, net of related tax effects, are as follows:

	June 30, 2021		December 31, 2020
Net unrealized gains on investment securities available-for-sale	$	6.3	$	56.8
Net unrealized gains on investment securities transferred to held-to-maturity	18.5		—
Net unrealized loss on derivatives	(0.7)		(0.2)
Net accumulated other comprehensive gains	$	24.1	$	56.6