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Acquisition - PCI and Non-PCI Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Nov. 21, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
PCI loans
Less: interest component of cash flows expected to be collected (accretable yield)	$ 1,254		$ 1,476	$ 2,618	$ 4,027
Bank of Napa, N.A. (Napa)
Non-PCI loans
Contractually required payments including interest		$ 183,833
Contractual cash flows not expected to be collected		14,227
Fair value of non-PCI loans		133,865
Bank of Napa, N.A. (Napa) | Receivables Acquired with Deteriorated Credit Quality
PCI loans
Contractually required payments including interest		1,769
Less: contractual cash flows not expected to be collected (nonaccretable difference)		805
Cash flows expected to be collected (undiscounted)		964
Less: interest component of cash flows expected to be collected (accretable yield)		109
Fair value of PCI loans		$ 855

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The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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