Derivative Financial Instruments - Other Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Derivative assets:
Derivative asset, before netting	$ 178,612		$ 232,293
Netting	(6,681)		(119,217)
Total derivative assets	171,931		113,076
Derivative liabilities:
Derivative liability, before netting	79,305		102,881
Netting	(64,753)		(61,981)
Net amounts of liabilities presented in the consolidated balance sheet	14,552		40,900
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	106,774	$ (294,645)
Interest rate lock commitments and loans held for sale
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	(145,046)	52,237
Mortgage servicing rights
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	88,640	(294,334)
Margin Deposits
Derivative assets:
Collateral placed with (received from) derivative counterparties	58,072		(57,236)
Interest rate lock commitments
Derivative assets:
Total derivative assets	111,722		56,946
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Gains (losses) recognized on derivative financial instruments	76,377	$ (19,786)
Forward contracts | Purchases
Derivative Instruments
Notional amount	12,030,348		12,760,764
Derivative assets:
Derivative asset, before netting	18,531		3,701
Derivative liabilities:
Derivative liability, before netting	1,748		66,646
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	12,760,764
Balance at end of quarter	12,030,348
Forward contracts | Sales
Derivative Instruments
Notional amount	20,823,643		23,440,334
Derivative assets:
Derivative asset, before netting	7,339		152,526
Derivative liabilities:
Derivative liability, before netting	69,129		12,854
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	23,440,334
Balance at end of quarter	20,823,643
Forward contracts | Sales | PennyMac Mortgage Investment Trust
Derivative Instruments
Notional amount	59,541
Derivative liabilities:
Derivative liability, before netting	741
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at end of quarter	59,541
MBS put options
Derivative Instruments
Notional amount	500,000		450,000
Derivative assets:
Derivative asset, before netting	1		3,278
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	450,000
Balance at end of quarter	500,000
Put options on Eurodollar futures | Purchases
Derivative Instruments
Notional amount	13,325,000		4,270,000
Derivative assets:
Derivative asset, before netting	15,308		12,592
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	4,270,000
Balance at end of quarter	13,325,000
Put options on Eurodollar futures | Sales
Derivative Instruments
Notional amount	3,250,000
Derivative liabilities:
Derivative liability, before netting	1,523
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at end of quarter	3,250,000
Call options on Eurodollar futures | Purchases
Derivative Instruments
Notional amount	9,550,000		7,600,000
Derivative assets:
Derivative asset, before netting	25,711		3,250
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	7,600,000
Balance at end of quarter	9,550,000
Call options on Eurodollar futures | Sales
Derivative Instruments
Notional amount	800,000
Derivative liabilities:
Derivative liability, before netting	5,125
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at end of quarter	800,000
Treasury future | Purchases
Derivative Instruments
Notional amount	7,951,000		7,467,000
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	7,467,000
Balance at end of quarter	7,951,000
Treasury future | Sales
Derivative Instruments
Notional amount	9,380,000		10,521,000
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	10,521,000
Balance at end of quarter	9,380,000
Not designated as hedging instrument | Interest rate lock commitments
Derivative Instruments
Notional amount	9,890,968		7,801,677
Derivative assets:
Derivative asset, before netting	111,722		56,946
Derivative liabilities:
Derivative liability, before netting	1,780		$ 23,381
Activity for derivative contracts used to hedge the IRLCs and inventory of mortgage loans at notional value
Balance at beginning of quarter	7,801,677
Balance at end of quarter	$ 9,890,968