Fair Value Option (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Fair Value Disclosures [Abstract]
Other Borrowings, Fair Value Disclosure	$ 117,196	$ 118,838
Borrowings - Credit-Link Notes	118,100
Aggregate Unpaid Principal Balance in Excess of (Less Than) Fair Value	$ 929	$ 301

Aggregate Unpaid Principal Balance in Excess of (Less Than) Fair Value

No definition available.

Name:	pacw_AggregateUnpaidPrincipalBalanceInExcessOfLessThanFairValue
Namespace Prefix:	pacw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant