MORTGAGE BANKING OPERATIONS - Servicing Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Servicing fees and other	$ 35,342	$ 32,037	$ 39,561
Changes in fair value of single family MSRs due to modeled amortization	(19,669)	(17,754)	(20,670)
Amortization of multifamily and SBA MSRs	(7,581)	(5,657)	(5,214)
Net servicing income	8,092	8,626	13,677
Changes in fair value of MSRs due to changes in market inputs and/or assumptions	7,379	(19,955)	(16,224)
Mortgage servicing rights, risk management	(859)	865	(1,789)
Loan servicing income, discontinued operations	0	0	(2,103)
Loan servicing income	7,233	9,491	9,785
Servicing Contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net gain (loss) from derivatives hedging	$ (8,238)	$ 20,820	14,435
Single family residential mortgage servicing rights \| Single family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain (loss) in income during period from discontinued operations before income taxes			$ (900)

Changes in the fair value of mortgage servicing rights due to modeled amortization.

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Disposal Group, Including Discontinued Operation, Servicing Fees Net1

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Changes in MSR fair value due to changes in model inputs and assumptions, net of risk management derivatives.

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Servicing and other related fees, net of payments.

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Servicing fees and other.

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Servicing Fees Net, Including Discontinued Operations

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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