Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2019

Accounting Policies [Abstract]

Summary of amounts in income tax expense related to investments in qualifying affordable housing projects

The table below summarizes the amounts in income tax expense related to ASB’s LIHTC investments:

Years ended December 31	2019			2018			2017
(in millions)
Amounts in income taxes related to low-income housing tax credit investments
Amortization recognized in the provision for income taxes	$	(7.9	)	$	(7.7	)	$	(7.4	)
Tax credits and other tax benefits recognized in the provision for income taxes	11.9			10.9			10.7
Net benefit to income tax expense	$	4.0		$	3.2		$	3.3