Acquisitions - Narrative (Details) $ in Thousands			9 Months Ended
	Oct. 01, 2017 USD ($) branch shares	Oct. 01, 2016 USD ($) branch shares	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Deposit on acquisition of bank			$ 0	$ 9,470
Goodwill			$ 40,311		$ 40,231
Core deposits
Business Acquisition [Line Items]
Acquired finite-lived intangible assets useful life			10 years
Sierra Vista Bank
Business Acquisition [Line Items]
Total assets		$ 155,154
Equity interest issued (in shares) | shares		1,059,000
Deposit on acquisition of bank		$ 9,469
Goodwill		10,314
Core deposit intangible		$ 508
Increase to goodwill measurement adjustment			$ 80
Sierra Vista Bank | Folsom, California
Business Acquisition [Line Items]
Number of branches acquired | branch		1
Sierra Vista Bank | Fair Oaks, California
Business Acquisition [Line Items]
Number of branches acquired | branch		1
Sierra Vista Bank | Cameron Park, California
Business Acquisition [Line Items]
Number of branches acquired | branch		1
Folsom Lake Bank | Subsequent Event [Member]
Business Acquisition [Line Items]
Number of branches acquired | branch	3
Total assets	$ 197,300
Equity interest issued (in shares) | shares	1,276,888
Consideration transferred	$ 28,500