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Acquisitions - Schedule of Acquired loans with credit impairment (Details) - USD ($) $ in Millions | Aug. 16, 2018 | May 30, 2017
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Bank of the Cascades |  |
Business Acquisition [Line Items] |  |
Contractually required principal and interest payments |  | $ 49.7
Contractual cash flows not expected to be collected (“non-accretable discount”) |  | 24.7
Cash flows expected to be collected |  | 25.0
Interest component of cash flows expected to be collected (“accretable discount”) |  | 1.9
Fair value of acquired credit-impaired loans |  | $ 23.1
Inland Northwest Bank |  |
Business Acquisition [Line Items] |  |
Contractually required principal and interest payments | $ 27.5 |
Contractual cash flows not expected to be collected (“non-accretable discount”) | 4.4 |
Cash flows expected to be collected | 23.1 |
Interest component of cash flows expected to be collected (“accretable discount”) | 3.2 |
Fair value of acquired credit-impaired loans | $ 19.9 |

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- Definition The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. 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. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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