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Goodwill and Other Intangible Assets (Changes in the Carrying amount of Goodwill by Reporting Unit) (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Goodwill [Line Items] |  |
Beginning Balance | $ 465,547 | $ 469,433
Ending Balance | 465,697 | 465,547
Enstream Capital Markets, LLC |  |
Goodwill [Line Items] |  |
Acquisition of Enstream Capital Markets, LLC | 150 |
Desert Community Bank |  |
Goodwill [Line Items] |  |
Disposition of the DCB branches |  | (3,886)
Consumer and Business Banking |  |
Goodwill [Line Items] |  |
Beginning Balance | 353,321 | 357,207
Ending Balance | 353,321 | 353,321
Consumer and Business Banking | Enstream Capital Markets, LLC |  |
Goodwill [Line Items] |  |
Acquisition of Enstream Capital Markets, LLC | 0 |
Consumer and Business Banking | Desert Community Bank |  |
Goodwill [Line Items] |  |
Disposition of the DCB branches |  | (3,886)
Commercial Banking |  |
Goodwill [Line Items] |  |
Beginning Balance | 112,226 | 112,226
Ending Balance | 112,376 | 112,226
Commercial Banking | Enstream Capital Markets, LLC |  |
Goodwill [Line Items] |  |
Acquisition of Enstream Capital Markets, LLC | $ 150 |
Commercial Banking | Desert Community Bank |  |
Goodwill [Line Items] |  |
Disposition of the DCB branches |  | $ 0

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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- Definition Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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