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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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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.

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Business Combinations and Asset Acquisitions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Feb. 28, 2023
Asset Acquisition [Line Items]
Goodwill	$ 1,029,234		$ 1,029,234
Business Combination, Acquisition Related Costs	4,478	$ 115,898
Umpqua Bank and Columbia Banking System Merger
Asset Acquisition [Line Items]
Goodwill				$ 1,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill				$ 710,200
Business Combination, Acquisition Related Costs	$ 4,500	$ 115,900