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v3.19.3.a.u2

Summary of Significant Accounting Policies (Details) | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2019 USD ($) location | Jan. 01, 2020 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Accounting Policies [Line Items] |  |  |  |  |
Number Of Branch Locations | location | 146 |  |  |  |
FHLB membership stock purchase requirement cap | $ 10,000,000 |  |  |  |
Federal Home Loan Bank stock, par value | 100 |  |  |  |
Loans and Leases Receivable, Nonaccrual Loans Considered Impaired | 500,000 |  |  |  |
Loans and Leases Receivable, Loans Evaluated For Impairment On Quarterly Basis, Outstanding | $ 500,000 |  |  |  |
Number Of Days Used To Determine Treatment As Cash Equivalent | 90 days |  |  |  |
Number of Days of Delinquency at Which Loans Are Categorized As Non Accrual Status | 90 days |  |  |  |
Core Deposits [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Estimated life of CDI, in years | 10 years |  |  |  |
WASHINGTON |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Number Of Branch Locations | location | 71 |  |  |  |
OREGON |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Number Of Branch Locations | location | 61 |  |  |  |
IDAHO |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Number Of Branch Locations | location | 14 |  |  |  |
Vehicles [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P5Y |  |  |  |
Minimum [Member] | Building and Building Improvements [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P5Y |  |  |  |
Minimum [Member] | Furniture and Fixtures [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P3Y |  |  |  |
Minimum [Member] | Software [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P3Y |  |  |  |
Maximum [Member] | Building and Building Improvements [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P39Y |  |  |  |
Maximum [Member] | Furniture and Fixtures [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P7Y |  |  |  |
Maximum [Member] | Software [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives | P5Y |  |  |  |
Accounting Standards Update 2016-02 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Change in other assets due to adoption of new ASU | $ 49,200,000 |  |  |  |
Change in other liabilities due to adoption of new ASU | 48,200,000 |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ (782,000) |  |
Accounting Standards Update 2016-02 [Member] | Retained Earnings [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ (782,000) |  |
Accounting Standards Update 2018-02 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | $ 0
Accounting Standards Update 2018-02 [Member] | Retained Earnings [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | (4,082,000)
Accounting Standards Update 2016-09 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | (67,000)
Accounting Standards Update 2016-09 [Member] | Retained Earnings [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | 117,000
Accounting Standards Update 2016-09 [Member] | Common Stock [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  |  | $ (184,000)
Accounting Standards Update 2016-01 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  | $ 0 |
Accounting Standards Update 2016-01 [Member] | Retained Earnings [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  |  | $ 157,000 |
Accounting Standards Update 2018-15 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Change in other assets due to adoption of new ASU | 1,500,000 |  |  |  |
Accounting Standards Update 2016-13 [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Change in allowance for credit loss due to adoption of new ASU |  | $ 1,600,000 |  |  |
Change in allowance for unfunded commitments and letters of credit due to adoption of new ASU |  | $ 1,600,000 |  |  |
Accounting Standards Update 2016-13 [Member] | Retained Earnings [Member] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 2,500,000 |  |  |  |
Designated as Hedging Instrument [Member] | Interest rate collar [Domain] |  |  |  |  |
Accounting Policies [Line Items] |  |  |  |  |
Derivative, Notional Amount | $ 500,000,000.0 |  |  |  |

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