v3.25.3

MORTGAGE SERVICING RIGHTS - Fair Value Disclosures (Detail) - MSRs - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Servicing
Fair value of the MSRs	$ 1,400.0	$ 1,400.0
Sensitivity Analysis of Fair Value, example 1, impact of percent adverse change in discount rate, percent	1.00%
Decrease in fair value as a result of 100 basis point increase in discount rate	$ 40.6
Sensitivity Analysis of Fair Value, example 2, impact of percent adverse change in discount rate, percent	2.00%
Decrease in fair value as a result of 200 basis point increase in discount rate	$ 78.4
Sensitivity Analysis of Fair Value, example 1, impact of percent adverse change in placement fee rate, percent	0.50%
Decrease in fair value as a result of 50 basis point decrease in placement fee rate	$ 49.5
Sensitivity Analysis of Fair Value, example 2, impact of percent adverse change in placement fee rate, percent	1.00%
Decrease in fair value as a result of 100 basis point decrease in placement fee rate	$ 99.0

Fair value 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://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(5)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)(6)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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- Definition

The hypothetical financial impact of a .5 percent adverse change in the placement fee rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

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- Definition

The hypothetical financial impact of a 1 percent adverse change in the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

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- Definition

The hypothetical financial impact of a 2 percent adverse change in the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

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The hypothetical financial impact of a 1 percent adverse change in the placement fee rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

No definition available.

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- Definition

A specified percentage variance in the discount rate assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date, sensitivity scenario 1.

+ References

No definition available.

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A specified percentage variance in the placement fee rate assumption in the determination of fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date, sensitivity scenario 1.

+ References

No definition available.

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Walker & Dunlop, Inc. 10-Q