Subordinated Debentures (Details)		1 Months Ended		3 Months Ended
	Nov. 01, 2017 USD ($) notes	Aug. 31, 2014 USD ($)	Mar. 31, 2004 USD ($)	Mar. 31, 2018 USD ($)	Apr. 01, 2017 USD ($)
PPBI Trust I
Subordinated Debentures
Floating Rate Trust Preferred Securities issue amount			$ 10,000,000
Notes
Subordinated Debentures
Debt issued		$ 60,000,000
Fixed interest rate (as a percent)		5.75%
Contribution of net proceeds from the Private Placement to the Bank to support general corporate purposes		$ 50,000,000
Subordinated Debentures
Subordinated Debentures
Floating interest rate, base rate				three-month LIBOR
Effective rate (as a percent)				4.47%
Subordinated Debentures | Mission Community Capital Trust I
Subordinated Debentures
Effective rate (as a percent)				4.67%
Floating rate junior subordinated debt				$ 2,800,000	$ 3,100,000
Purchase accounting fair value adjustments				$ 321,000
Subordinated Debentures | Santa Lucia Bancorp (CA) Capital Trust
Subordinated Debentures
Effective rate (as a percent)				3.20%
Floating rate junior subordinated debt				$ 3,800,000	5,200,000
Purchase accounting fair value adjustments				$ 1,400,000
Subordinated Debentures | Heritage Oaks Bancorp
Subordinated Debentures
Effective rate (as a percent)				3.41%
Floating rate junior subordinated debt				$ 3,900,000	$ 5,200,000
Purchase accounting fair value adjustments				$ 1,300,000
Subordinated Debentures | LIBOR
Subordinated Debentures
Floating interest rate, basis points added to base rate (as a percent)				2.75%
Subordinated Debentures | LIBOR | Mission Community Capital Trust I
Subordinated Debentures
Floating interest rate, basis points added to base rate (as a percent)				2.95%
Subordinated Debentures | LIBOR | Santa Lucia Bancorp (CA) Capital Trust
Subordinated Debentures
Floating interest rate, basis points added to base rate (as a percent)				1.48%
Subordinated Debentures | LIBOR | Heritage Oaks Bancorp
Subordinated Debentures
Floating interest rate, basis points added to base rate (as a percent)				1.72%
Subordinated Debentures | PPBI Trust I
Subordinated Debentures
Debt issued			$ 10,300,000.0
Minority interest purchased (as a percent)			3.00%
Amount of minority interest purchased			$ 310,000
Subordinated Notes 7.125% | Plaza Bancorp
Subordinated Debentures
Fixed interest rate (as a percent)	7.125%
Number of subordinated notes assumed | notes	3
Debt assumed in acquisition	$ 25,000,000
Redemption price (as a percent)	103.00%
Redemption price, subsequent reduction (as a percent)	50.00%