NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 2) (USD $)	Dec. 31, 2012
Minimum
Non-covered impaired loans and leases by portfolio segment and class
Threshold of unpaid principal balance of non-covered nonaccrual loans and leases for individual evaluation of impairment	$ 250,000
Maximum
Non-covered impaired loans and leases by portfolio segment and class
Threshold of unpaid principal balance of non-covered nonaccrual loans and leases for collective evaluation of impairment	$ 250,000

Represents the threshold of unpaid principal balance of non-covered nonaccrual loans which are reviewed collectively for impairment.

No definition available.

Name:	pacw_ImpairedFinancingReceivableThresholdOfUnpaidPrincipalBalanceForCollectiveEvaluationOfImpairment
Namespace Prefix:	pacw_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant