OTHER COMPREHENSIVE INCOME

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



Year ended December 31, 2017	Before Tax Amount			Tax Expense (Benefit)			Net of Tax Amount
Investment securities available-for sale:
Change in net unrealized loss during period	$	(6.5	)	$	(2.7	)	$	(3.8	)
Reclassification adjustment for net gains included in net income	(0.7		)	(0.3		)	(0.4		)
Change in unamortized loss on available-for-sale securities transferred into held-to-maturity	1.8			0.7			1.1
Change in net unrealized loss on derivatives	(1.1		)	(0.4		)	(0.7		)
Reclassification adjustment for derivative net (gains) losses included in net income	1.1			0.4			0.7
Defined benefits post-retirement benefit plan:
Change in net actuarial loss (gain)	(1.2		)	(0.5		)	(0.7		)
Total other comprehensive loss	$	(6.6	)	$	(2.8	)	$	(3.8	)



Year ended December 31, 2016	Before Tax Amount			Tax Expense (Benefit)			Net of Tax Amount
Investment securities available-for sale:
Change in net unrealized loss during period	$	(19.4	)	$	(7.6	)	$	(11.8	)
Reclassification adjustment for net gains included in net income	(0.3		)	(0.1		)	(0.2		)
Unamortized premium on available-to-sale securities transferred into held-for-maturity	1.9			0.7			1.2
Change in net unrealized gain on derivatives	(0.2		)	(0.1		)	(0.1		)
Defined benefits post-retirement benefit plan:
Change in net actuarial loss	4.0			1.6			2.4
Total other comprehensive loss	$	(14.0	)	$	(5.5	)	$	(8.5	)



Year ended December 31, 2015	Before Tax Amount			Tax Expense (Benefit)			Net of Tax Amount
Investment securities available-for sale:
Change in net unrealized loss during period	$	3.1		$	1.2		$	1.9
Reclassification adjustment for net gains included in net income	(0.2		)	(0.1		)	(0.1		)
Change in unamortized gain on available-for-sale securities transferred into held-to-maturity	1.6			0.6			1.0
Change in net unrealized gain on derivatives	0.2			0.1			0.1
Defined benefits post-retirement benefit plan:
Change in net actuarial loss	0.1			0.1			—
Total other comprehensive income	$	4.8		$	1.9		$	2.9

The components of accumulated other comprehensive income (loss), net of income taxes, are as follows:



Year ended December 31,	2017			2016
Net unrealized gain (loss) on investment securities available-for-sale	$	(13.2	)	$	(10.1	)
Net actuarial gain (loss) on defined benefit post-retirement benefit plans	1.3			2.0
Net unrealized gain (loss) on derivatives	—			—
Net accumulated other comprehensive income (loss)	$	(11.9	)	$	(8.1	)