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Acquisition Acquisitions (Details) - USD ($) shares in Millions, $ in Millions		3 Months Ended
	Oct. 01, 2018	Sep. 30, 2018
Cobiz Financial Inc. [Member]
Business Acquisition [Line Items]
Cobiz Financial Loans		$ 3,100.0
Cobiz Financial Assets		3,900.0
Cobiz Financial Deposits		3,300.0
Cobiz Financial Equity		$ 339.0
Switchgrass Holdings LLC [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		May 01, 2018
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred		$ 14.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles		$ 6.7
Subsequent Event [Member] | Cobiz Financial Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Oct. 01, 2018
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred	$ 944.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash Paid	$ 242.0
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Shares Issued as Consideration	7.2
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Share Value Transferred	$ 702.0

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Cobiz Financial Assets

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Cobiz Financial Deposits

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Cobiz Financial Equity

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Cobiz Financial Loans

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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