Goodwill and Other Intangible Assets (Goodwill Reporting Unit) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 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

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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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.

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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.

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