Fair Value Measurements (Fair Value Mortgage Loans Held For Sale Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Mortgage loans held for sale, measured at fair value	$ 48,705		$ 48,705		$ 61,614
Mortgage loans held for sale, amortized cost	47,464		47,464		59,313
Mortgage loans held for sale, difference between fair value and amortized cost	1,241		1,241		$ 2,301
Mortgage Loans Held for Sale [Member]
Change in fair value under fair value option election	$ 372	$ 1,100	$ (1,100)	$ 2,200

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=120238483&loc=d3e48678-111004

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- Definition

The difference between the fair value and principal amount of mortgage loans held for sale.

+ References

No definition available.

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