Other Assets (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Other Assets [Abstract]
Unamortized portion of investments in affordable housing limited partnerships	$ 37.5	$ 37.5

Investments in low income housing tax credit entities.

No definition available.

Name:	hwc_InvestmentsInLowIncomeHousingTaxCreditEntities
Namespace Prefix:	hwc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant