Fair Value Measurement (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Loans and leases, at fair value	$ 353,900		$ 353,900
Unrealized (losses) gains arising during the period	(11,946)	$ (14,555)	(44,504)	$ 26,857
Changes in unrealized gains and losses on junior subordinated debentures carried at fair value, net of taxes	(8,874)	(10,811)	(33,058)	19,950
Goodwill Impairment Adjustment				1,800,000
Residential Mortgage Banking Revenue
Fair Value, Option, Quantitative Disclosures [Line Items]
Net increase (decrease) in fair value	(4,500)	$ 2,200	(13,500)	$ 16,500
Other Income
Fair Value, Option, Quantitative Disclosures [Line Items]
Net increase (decrease) in fair value	$ 3,400		$ 5,700

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Goodwill Impairment Adjustment

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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after tax, before reclassification adjustment, of unrealized gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

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Amount, before tax and reclassification adjustment, of unrealized gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

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