Loans and Credit Quality - Narrative (Details)		12 Months Ended
	Apr. 01, 2014 USD ($) purchased_loan	Dec. 31, 2016 USD ($) financing_commitment contract	Dec. 31, 2015 USD ($) contract	Dec. 31, 2014 USD ($) contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans secured by real estate		74.00%
Loans unsecured		3.00%
Loans secured for general commercial uses		23.00%
Net nonaccrual loans		$ 12,480,000	$ 2,125,000
Interest income earned on nonaccrual loans		676,000	276,000	$ 218,000
Interest income earned on nonaccrual loans with no balance		181,000	617,000	350,000
Greater than 90 days still accruing		456,000	0
Recorded investment in loans considered to be impaired		38,656,000	34,640,000
Impaired loan, average recorded investment		42,599,000	25,997,000	10,500,000
Impaired loan, interest income on accrual method		2,354,000	1,140,000	$ 762,000
Loans classified as troubled debt restructuring		$ 16,219,000	13,740,000
Commitment to Lend | financing_commitment		0
Write down on TDR		$ 0	$ 304,000
TDR with specific impairment | contract		4	0
TDR that subsequently defaulted, recorded investment | contract		0	0	0
Loans pledged as collateral		$ 0	$ 0
Unfunded loan commitments		15,000	0
Alaska Pacific Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchased impaired loans | purchased_loan	18
Accretable difference on purchased loans	$ 0
Fair value of purchased credit impaired loans	$ 3,900,000	$ 1,100,000	$ 1,600,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recovery time for market		18 years
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recovery time for market		24 years