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Goodwill and Other Intangible Assets (Goodwill Reporting Unit) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Goodwill [Roll Forward] |  |
Goodwill, beginning | $ 465,547 | $ 469,433
Goodwill, end | 465,697 | 465,547
Enstream Capital Markets, LLC |  |
Goodwill [Roll Forward] |  |
Acquisition of Enstream Capital Markets, LLC | 150 |
Desert Community Bank |  |
Goodwill [Roll Forward] |  |
Disposition of the DCB branches |  | (3,886)
Consumer and Business Banking |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning | 353,321 | 357,207
Goodwill, end | 353,321 | 353,321
Consumer and Business Banking | Enstream Capital Markets, LLC |  |
Goodwill [Roll Forward] |  |
Acquisition of Enstream Capital Markets, LLC | 0 |
Consumer and Business Banking | Desert Community Bank |  |
Goodwill [Roll Forward] |  |
Disposition of the DCB branches |  | (3,886)
Commercial Banking |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning | 112,226 | 112,226
Goodwill, end | 112,376 | 112,226
Commercial Banking | Enstream Capital Markets, LLC |  |
Goodwill [Roll Forward] |  |
Acquisition of Enstream Capital Markets, LLC | $ 150 |
Commercial Banking | Desert Community Bank |  |
Goodwill [Roll Forward] |  |
Disposition of the DCB branches |  | $ 0

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