MORTGAGE SERVICING RIGHTS - Schedule of Activity Related to Capitalized MSRs (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Mortgage Servicing Rights
Beginning balance			$ 718,799
Ending balance	$ 778,269		778,269
MSRs
Mortgage Servicing Rights
Beginning balance	722,486	$ 677,946	718,799	$ 670,146
Additions, following sale of loan	99,589	48,695	143,803	95,797
Amortization	(36,706)	(34,267)	(71,924)	(68,470)
Pre-payments and write-offs	(7,100)	(4,347)	(12,409)	(9,446)
Ending balance	$ 778,269	$ 688,027	$ 778,269	$ 688,027

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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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
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-Paragraph 4
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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