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Commitments and Contingencies (Details) $ / shares in Units, $ in Millions | Apr. 25, 2018 USD ($) office $ / shares | Mar. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | May 30, 2017 $ / shares
--- | --- | --- | --- | ---
Loss Contingencies [Line Items] |  |  |  |
Notional amount of terminated commitment |  | $ 466.2 | $ 433.0 |
Price per share (in dollars per share) | $ / shares |  |  |  | $ 34.30
Mortgage Loans Held for Sale |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Mortgage loans with recourse provision in effect |  | 0.6 |  |
Construction Contracts |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Commitments under construction contracts |  | $ 1.2 |  |
Subsequent Event | INB |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Date of agreement and plan for merger with Cascade Bancorp | Apr. 25, 2018 |  |  |
Number of banking offices acquired | office | 20 |  |  |
All-stock transaction value | $ 160.9 |  |  |
Price per share (in dollars per share) | $ / shares | $ 21.03 |  |  |

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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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