Mortgage Servicing Rights ("MSRs") (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Servicing Asset at Fair Value, Amount [Roll Forward]
Fair value at beginning of the period	$ 230,225	$ 147,571
Additions from loans sold with servicing retained	5,107	14,401
Estimate of changes in fair value due to:
Early buyout options (“EBO”) exercised	0	(175)
Payoffs and paydowns	(3,909)	(6,016)
Changes in valuation inputs or assumptions	(6,953)	43,365
Fair value at end of the period	224,470	199,146
Unpaid principal balance of mortgage loans serviced for others	$ 14,080,461	$ 13,426,535

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
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- References

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Servicing Asset At Fair Value, Early Buyout Option

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- Definition

Servicing Assets At Fair Value, Additions From Loans Sold With Servicing Retained

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No definition available.

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