Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2021

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	2021		2020		2019
(in millions)
Amounts in income taxes related to low-income housing tax credit investments
Amortization recognized in the provision for income taxes	$	(10.3)	$	(9.6)	$	(7.9)
Tax credits and other tax benefits recognized in the provision for income taxes	13.9		13.7		11.9
Net benefit to income tax expense	$	3.6	$	4.1	$	4.0