Fair Value Option (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Other Borrowings, Fair Value Disclosure	$ 119,624	$ 123,116
Borrowings - Credit-Link Notes	120,600
Aggregate Unpaid Principal Balance in Excess of (Less Than) Fair Value	$ 993	$ 1,479

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