Benefit Plans - 401(k) Plan (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Employer's match of employees' contributions of the first 3% of eligible compensation (as a percent)	100.00%	100.00%	100.00%
Percentage of eligible compensation, matched 100% by employer	3.00%	3.00%	3.00%
Employer's match of employees' contributions of the next 2% of eligible compensation (as a percent)	50.00%	50.00%	50.00%
Percentage of eligible compensation, matched 50% by employer	2.00%	2.00%	2.00%
Contributions made	$ 2.9	$ 2.5	$ 1.4
Minimum
Defined Benefit Plan Disclosure [Line Items]
Employee contribution, as a percentage of compensation	1.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Employee contribution, as a percentage of compensation	99.00%

Represents the annual employee contributions to the plan as a percentage of compensation.

No definition available.

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Namespace Prefix:	ppbi_
Data Type:	num:percentItemType
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- Definition

Represents the first level of employees' contributions (percentage of compensation), which are matched by the employer.

+ References

No definition available.

+ Details

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- Definition

Represents the second level of employees' contributions (percentage of compensation), which are matched by the employer.

+ References

No definition available.

+ Details

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Namespace Prefix:	ppbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the employer's matching contribution of the first level of employees' contributions.

+ References

No definition available.

+ Details

Name:	ppbi_DefinedContributionPlanEmployersMatchLevelOne
Namespace Prefix:	ppbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the employer's matching contribution of the second level of employees' contributions.

+ References

No definition available.

+ Details

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Namespace Prefix:	ppbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

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