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Derivative Instruments (Schedule Of Notional Amounts Of Derivative Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Derivative [Line Items]
Derivative, Notional Amount	$ 5,182,136	$ 4,593,942
Interest rate swaps
Derivative [Line Items]
Derivative, Notional Amount	2,063,942	1,968,679
Interest Rate Floor
Derivative [Line Items]
Derivative, Notional Amount	2,500,000	2,000,000
Interest rate caps
Derivative [Line Items]
Derivative, Notional Amount	120,000	105,770
Credit risk participation agreements
Derivative [Line Items]
Derivative, Notional Amount	473,785	474,951
Foreign exchange contracts
Derivative [Line Items]
Derivative, Notional Amount	14,817	29,451
Mortgage loan commitments
Derivative [Line Items]
Derivative, Notional Amount	5,252	6,297
Mortgage loan forward sale contracts
Derivative [Line Items]
Derivative, Notional Amount	840	1,794
Forward TBA contracts
Derivative [Line Items]
Derivative, Notional Amount	$ 3,500	$ 7,000

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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