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Segment Reporting (Narrative) (Details) $ in Thousands	6 Months Ended
Segment Reporting (Narrative) (Details) $ in Thousands	Jun. 30, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jan. 31, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment	3
Deposits	$ 58,747,532	$ 54,054,340
Goodwill	$ 2,631,465	$ 2,514,104	$ 2,514,104			$ 538,373
Sterling
Segment Reporting Information [Line Items]
Goodwill				$ 1,914,204	$ 1,900,000
Commercial Banking \| Sterling
Segment Reporting Information [Line Items]
Goodwill				1,700,000
Consumer Banking \| Sterling
Segment Reporting Information [Line Items]
Goodwill				$ 200,000
HSA Bank \| Bend
Segment Reporting Information [Line Items]
Goodwill					$ 35,700