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Segment Reporting Segment Reporting Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) Segment	Jan. 31, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| Segment	3
Goodwill	$ 2,514,104			$ 538,373	$ 538,373
Deposits	54,054,340			29,847,029
Sterling
Segment Reporting Information [Line Items]
Goodwill		$ 1,939,765
Commercial Banking [Member] \| Sterling
Segment Reporting Information [Line Items]
Goodwill		1,700,000
Community Banking [Member]
Segment Reporting Information [Line Items]
Deposits			$ 125,400
Community Banking [Member] \| Sterling
Segment Reporting Information [Line Items]
Goodwill		$ 200,000
Community Banking [Member] \| Assets Under Administration
Segment Reporting Information [Line Items]
Fair Value Disclosure, off-Balance-Sheet Risks, Amount, Asset			4,300,000
HSA Bank [Member] \| Bend
Segment Reporting Information [Line Items]
Goodwill			$ 36,000
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 0			$ 0