Fair Value - Summary of Changes in Items Measured Using Level 3 Inputs on Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Assets:
Servicing received as proceeds from sales of mortgage loans	$ 3,300	$ 1,906
Recurring [Member]
Assets:
Beginning balance	2,584,642	2,453,768
Purchases and issuances	3,284	288,393
Repayments and sales	(112,659)	(58,613)
Capitalization of interest	30,309	10,209
Accrual of interest		3,752
ESS received pursuant to a recapture agreement with PFSI	1,911	1,246
Interest rate lock commitments issued, net	10,698	19,400
Servicing received as proceeds from sales of mortgage loans	3,300	1,906
Proceeds from CRT Agreements	2,536
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	12,466	7,206
Other factors	(14,955)	(7,360)
Total	(2,489)	(154)
Transfers of mortgage loans to REO and real estate held for investment	(58,455)
Transfers of mortgage loans to REO		(79,695)
Transfers of interest rate lock commitments to mortgage loans acquired for sale	(26,675)	(16,859)
Ending balance	2,436,402	2,623,353
Changes in fair value recognized during the period relating to assets	(3,329)	15,527
CRT Agreements [Member] \| Recurring [Member]
Assets:
Beginning balance	593
Purchases and issuances	0
Repayments and sales	(668)
Capitalization of interest	0
ESS received pursuant to a recapture agreement with PFSI	0
Interest rate lock commitments issued, net	0
Servicing received as proceeds from sales of mortgage loans	0
Proceeds from CRT Agreements	2,536
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	0
Other factors	(6,679)
Total	(6,679)
Transfers of mortgage loans to REO and real estate held for investment	0
Transfers of interest rate lock commitments to mortgage loans acquired for sale	0
Ending balance	(4,218)
Changes in fair value recognized during the period relating to assets	(6,679)
Interest Rate Lock Commitments [Member] \| Recurring [Member]
Assets:
Beginning balance	4,646	5,661
Purchases and issuances	0	0
Repayments and sales	0	0
Capitalization of interest	0	0
Accrual of interest		0
ESS received pursuant to a recapture agreement with PFSI	0	0
Interest rate lock commitments issued, net	10,698	19,400
Servicing received as proceeds from sales of mortgage loans	0	0
Proceeds from CRT Agreements	0
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	0	0
Other factors	20,666	12
Total	20,666	12
Transfers of mortgage loans to REO and real estate held for investment	0
Transfers of mortgage loans to REO		0
Transfers of interest rate lock commitments to mortgage loans acquired for sale	(26,675)	(16,859)
Ending balance	9,335	8,214
Changes in fair value recognized during the period relating to assets	9,335	8,214
Interest-only security payable [Member] \| Recurring [Member]
Assets:
Beginning balance	0
Purchases and issuances	682
Repayments and sales	0
Capitalization of interest	0
ESS received pursuant to a recapture agreement with PFSI	0
Interest rate lock commitments issued, net	0
Servicing received as proceeds from sales of mortgage loans	0
Proceeds from CRT Agreements	0
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	0
Other factors	(7)
Total	(7)
Transfers of mortgage loans to REO and real estate held for investment	0
Transfers of interest rate lock commitments to mortgage loans acquired for sale	0
Ending balance	675
Changes in fair value recognized during the period relating to assets	(7)
Mortgage loans at fair value [Member] \| Recurring [Member]
Assets:
Beginning balance	2,100,394	2,199,583
Purchases and issuances	0	241,981
Repayments and sales	(32,065)	(45,882)
Capitalization of interest	23,294	10,209
Accrual of interest		0
ESS received pursuant to a recapture agreement with PFSI	0	0
Interest rate lock commitments issued, net	0	0
Servicing received as proceeds from sales of mortgage loans	0	0
Proceeds from CRT Agreements	0
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	12,466	7,206
Other factors	1,929	9,980
Total	14,395	17,186
Transfers of mortgage loans to REO and real estate held for investment	(58,455)
Transfers of mortgage loans to REO		(79,695)
Transfers of interest rate lock commitments to mortgage loans acquired for sale	0	0
Ending balance	2,047,563	2,343,382
Changes in fair value recognized during the period relating to assets	17,676	24,665
Excess servicing spread [Member] \| Recurring [Member]
Assets:
Beginning balance	412,425	191,166
Purchases and issuances	0	46,412
Repayments and sales	(79,926)	(12,731)
Capitalization of interest	7,015	0
Accrual of interest		3,752
ESS received pursuant to a recapture agreement with PFSI	1,911	1,246
Interest rate lock commitments issued, net	0	0
Servicing received as proceeds from sales of mortgage loans	0	0
Proceeds from CRT Agreements	0
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	0	0
Other factors	(19,449)	(7,536)
Total	(19,449)	(7,536)
Transfers of mortgage loans to REO and real estate held for investment	0
Transfers of mortgage loans to REO		0
Transfers of interest rate lock commitments to mortgage loans acquired for sale	0	0
Ending balance	321,976	222,309
Changes in fair value recognized during the period relating to assets	(12,239)	(7,536)
Mortgage servicing rights [Member] \| Recurring [Member]
Assets:
Beginning balance	66,584	57,358
Purchases and issuances	2,602	0
Repayments and sales	0	0
Capitalization of interest	0	0
Accrual of interest		0
ESS received pursuant to a recapture agreement with PFSI	0	0
Interest rate lock commitments issued, net	0	0
Servicing received as proceeds from sales of mortgage loans	3,300	1,906
Proceeds from CRT Agreements	0
Changes in fair value included in income arising from:
Changes in instrument-specific credit risk	0	0
Other factors	(11,415)	(9,816)
Total	(11,415)	(9,816)
Transfers of mortgage loans to REO and real estate held for investment	0
Transfers of mortgage loans to REO		0
Transfers of interest rate lock commitments to mortgage loans acquired for sale	0	0
Ending balance	61,071	49,448
Changes in fair value recognized during the period relating to assets	$ (11,415)	$ (9,816)

Represents the change in fair value of Excess Spread Investment attributable to accrual of interest thereon.

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Represents excess servicing spread recapture received by the Company in settlement of its recapture agreement with an affiliate in compensation for the affiliate's refinancing of mortgage loans underlying excess servicing spread assets.

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Fair Value Measurement with Unobservable Inputs Reconciliation Recurring Basis Asset Purchases And Issuances

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Fair value measurement with unobservable inputs reconciliation recurring basis asset sales and settlements.

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Represents the change in fair value of mortgage loans attributable to capitalization of delinquent interest.

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No definition available.

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Changes in fair value of mortgage loans attributable to changes in inputs other than credit.

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Represents the fair value at issuance of interest rate lock commitments issued during the period.

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Proceeds From Payments For Credit Risk Transfer Agreements

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period from transfers of financial assets.

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No definition available.

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Transfer Of Interest Rate Lock Commitments To Mortgage Loans Acquired For Sale

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No definition available.

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- Definition

Represents the value of mortgage loans transferred to REO in settlement of the mortgage loans either through foreclosure or voluntary transfer of the property to the Company by the borrower.

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No definition available.

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Transfers of mortgage loans to REO and real estate held for investment.

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Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

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