Mortgage Servicing Rights ("MSRs") (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of the period	$ 199,146	$ 124,316	$ 147,571	$ 92,081
Additions from loans sold with servicing retained	11,210	17,512	25,611	42,128
Estimate of changes in fair value due to:
Early buyout options (“EBO”) exercised	(1)	(144)	(176)	(402)
Payoffs and paydowns	(6,838)	(8,540)	(12,854)	(18,708)
Changes in valuation inputs or assumptions	9,147	(5,540)	52,512	12,505
Fair value at end of the period	212,664	127,604	212,664	127,604
Unpaid principal balance of mortgage loans serviced for others	$ 13,643,623	$ 12,307,337	$ 13,643,623	$ 12,307,337

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

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

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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
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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
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Servicing Asset At Fair Value, Early Buyout Option

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

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