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Business Combinations (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Nov. 01, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Business Acquisition [Line Items] |  |  |  |  |
Threshold for average assets requiring CFPB examination |  | $ 10,000,000 |  | $ 10,000,000 |
Estimated pre-tax annual impact of no longer qualifying for the small issuer exemption from interchange fee cap |  |  |  | 10,000 |
Pacific Continental [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 2,822 | $ 1,023 | 7,087 | $ 2,387
Business Acquisition, Pro Forma Revenue |  |  |  |  | 278,119
Business Combination, Consideration Transferred | $ 637,103 |  |  |  |
Business Acquisition, Effective Date of Acquisition | Nov. 01, 2017 |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% |  |  |  |
Business Combination, Purchase Price Allocation, Goodwill Amount | $ 383,080 |  |  |  |
Business Combination, Purchase Price Allocation, Amortizable Intangible Assets | 46,875 |  |  |  |
Business Combination, Purchase Price Allocation, Other Assets | 50,638 |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets | 2,554,514 |  |  |  |
Business Combination, 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, Junior Subordinated Debentures | (14,434) |  |  |  |
Business combination, purchase price allocation, securities sold under agreements to repurchase | (1,617) |  |  |  |
Business Combination, Purchase Price Allocation, Other Liabilities | (28,653) |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities | (2,300,491) |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net | $ 254,023 |  |  |  |
business combinations, core deposit intangible percentage of core deposits | 2.34% |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents | $ 81,190 |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities | 449,291 |  |  |  |
Business Combination, Purchase Price Allocation, FHLB Stock | 7,084 |  |  |  |
Business Combination, Acquired Receivable, Fair Value | 1,873,987 |  |  |  |
Business Combination, Purchase Price Allocation, Accrued Interest Receivable | 7,827 |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment | 27,343 |  |  |  |
Business Combination, Purchase Price Allocation, Other Real Estate Owned | $ 10,279 |  |  |  |
Business Acquisition, Pro Forma Net Income (Loss) |  |  |  |  | $ 72,199
Business Acquisition, Pro Forma Earnings Per Share, Basic |  |  |  |  | $ 1.00
Business Acquisition, Pro Forma Earnings Per Share, Diluted |  |  |  |  | $ 1.00
Pacific Continental [Member] | Compensation and employee benefits [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 931 | 0 | 2,487 | $ 0
Pacific Continental [Member] | Occupancy [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 586 | 351 | 1,590 | 352
Pacific Continental [Member] | Advertising and promotion [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 22 | 11 | 534 | 17
Pacific Continental [Member] | Data processing [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 634 | 473 | 921 | 473
Pacific Continental [Member] | Legal and professional fees [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 216 | 119 | 791 | 1,430
Pacific Continental [Member] | Taxes, licenses and fees [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | 0 | 3 | 0 | 3
Pacific Continental [Member] | Other noninterest expenses [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquisition Related Costs |  | $ 433 | $ 66 | $ 764 | $ 112

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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=84229725&loc=d3e1043-128460 + Details
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