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Business Combinations (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Nov. 01, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Cost of Acquired Entity, Purchase Price, Total | $ 637,103 |  |  |
Business Combination, Acquisition Related Costs |  | $ 0 | $ 8,661 |
Business Acquisition, Effective Date of Acquisition | Nov. 01, 2017 |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents | $ 81,190 |  |  |
Business Acquisition, Purchase Price Allocation, Current Assets, Marketable Securities | 449,291 |  |  |
Business Acquisition, Purchase Price Allocation, FHLB Stock | 7,084 |  |  |
Business Combination, Acquired Receivable, Fair Value | 1,873,987 |  |  |
Business Acquisition, Purchase Price Allocation, Accrued Interest Receivable | 7,827 |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | 27,343 |  |  |
Business Acquisition, Purchase Price Allocation, Other Real Estate Owned | 10,279 |  |  |
Business Combination, Purchase Price Allocation, Amortizable Intangible Assets | 46,875 |  |  |
Business Combination, Purchase Price Allocation, Other Assets | 50,638 |  |  |
Business Acquisition, Purchase Price Allocation, Liabilities, Deposits | (2,118,982) |  |  |
Business Combination, Purchase Price Allocation, Federal Home Loan bank advances | 101,127 |  |  |
Business Combination, Purchase Price Allocation, Subordinated Debt | (35,678) |  |  |
Business combination, purchase price allocation, securities sold under agreements to repurchase | (1,617) |  |  |
Business Acquisition, Purchase Price Allocation, Other Noncurrent Liabilities | (28,653) |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | 254,023 |  |  |
Business Combination, Purchase Price Allocation, Goodwill Amount | $ 383,080 |  |  |
Business Acquisition, Pro Forma Revenue |  |  |  | $ 571,944
Business Acquisition, Pro Forma Net Income (Loss) |  |  |  | $ 149,859
Business Acquisition, Pro Forma Earnings Per Share, Basic |  |  |  | $ 2.23
Business Acquisition, Pro Forma Earnings Per Share, Diluted |  |  |  | $ 2.23
Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | $ 17,196
Compensation and employee benefits [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 3,620 |
Compensation and employee benefits [Member] | Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | 8,014
Occupancy [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 1,619 |
Occupancy [Member] | Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | 1,912
Advertising and promotion [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 537 | 467
Data processing [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 963 |
Data processing [Member] | Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | 1,555
Legal and professional fees [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 1,028 |
Legal and professional fees [Member] | Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | 4,618
Other noninterest expenses [Member] | Pacific Continental [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  | $ 0 | $ 894 |
Other noninterest expenses [Member] | Intermountain Community Bancorp [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Business Combination, Acquisition Related Costs |  |  |  | $ 630

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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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