The cash outflow to obtain 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. Rights may be obtained via (1) acquisition or assumption of a servicing obligation that does not relate to financial assets of the servicer or its consolidated affiliates; or (2) by originating mortgage loans and then (a) transferring the loans to a Variable Interest Entity (VIE) in a transaction that meets the necessary transfer and classification requirements, or (b) transferring the loans in a transaction that meets the requirements for sale accounting.

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

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Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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The weighted average estimated remaining life of servicing portfolio acquired from a third-party servicer.

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Amount of additions from transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of additions from purchases of new servicing assets, subsequently measured at amortized cost, from a third-party servicer.

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Adjustments which reduce (increase) the purchase price of additions of new servicing assets, subsequently measured at amortized cost, purchased from a third-party servicer.

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MORTGAGE SERVICING RIGHTS - Schedule of Activity Related to Capitalized MSRs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Mortgage Servicing Rights
Beginning balance	$ 412,348
Ending balance	521,930	$ 412,348
Purchase of mortgage servicing rights	43,097
Purchased servicing portfolio loans final unpaid principal balance	63,081,154	50,212,264	$ 59,121,989	$ 57,321,824	$ 51,040,752	$ 47,794,561	$ 47,713,739	$ 46,066,660	$ 44,031,890
MSRs
Mortgage Servicing Rights
Beginning balance	412,348	375,907
Additions, following sale of loan	181,032	135,441
Purchases	43,097
Amortization	(99,417)	(80,702)
Pre-payments and write-offs	(15,130)	(18,298)
Ending balance	521,930	$ 412,348
HUD Loan Portfolio Acquired
Mortgage Servicing Rights
Purchased servicing portfolio loans final unpaid principal balance	3,600,000
HUD Loan Portfolio Acquired \| MSRs
Mortgage Servicing Rights
Purchase of mortgage servicing rights	44,800
Adjustments reducing purchase price	1,700
Purchased servicing portfolio loans final unpaid principal balance	$ 3,600,000
Weighted average estimated remaining life of acquired servicing portfolio	10 years 10 months 24 days