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MORTGAGE BANKING OPERATIONS - Key Economic Assumptions (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
CPRs
Rates per annum [Abstract]
Servicing asset, measurement input	8.84%	11.37%	18.23%
Discount Rates
Rates per annum [Abstract]
Servicing asset, measurement input	8.23%	7.82%	9.31%

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- Definition

Rates per annum.

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- Definition

Servicing Asset, Weighted Average Measurement Input

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