CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Cash flow from operating activities
Net income	$ 394,246	$ 206,934
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Net gains on loans held for sale at fair value	(770,151)	(595,324)
Change in fair value of mortgage servicing rights and mortgage servicing liabilities	1,070,300	758,158
Mortgage servicing rights hedging results	(95,978)	224,371
Accrual of unearned discounts on principal-only stripped mortgage-backed securities	(31,676)	(29,219)
Capitalization of interest on loans held for sale	(1,839)	(362)
Amortization of debt issuance costs	24,835	21,860
Results of real estate acquired in settlement in loans	1,159	(330)
Change in fair value of investment in common shares of PennyMac Mortgage Investment Trust	24	51
Repricing of payable to exchanged Private National Mortgage Acceptance Company, LLC unitholders under tax receivable agreement	(1,092)
Stock-based compensation expense	28,531	21,314
Provision for servicing advance losses	22,100	13,974
Depreciation and amortization	41,583	42,165
Impairment of capitalized software	4,333
Amortization of operating lease right-of-use assets	10,555	10,256
Purchase of loans held for sale from PennyMac Mortgage Investment Trust	(52,856,500)	(57,502,461)
Purchase of loans held for sale from non-affiliates	(26,920,281)	(1,933,158)
Origination of loans held for sale	(18,739,010)	(12,069,838)
Purchase of loans from Ginnie Mae securities and early buyout investors	(3,412,426)	(2,379,099)
Sale to non-affiliates and principal payment of loans held for sale	95,792,613	70,706,054
Sale of loans held for sale to PennyMac Mortgage Investment Trust	5,673,014	191,250
Repurchase of loans subject to representations and warranties	(77,071)	(70,700)
Decrease in servicing advances	7,508	194,088
Increase in receivable from PennyMac Mortgage Investment Trust	(16,256)	(5,451)
Sale of real estate acquired in settlement of loans	53,576	37,840
Increase in other assets	(53,288)	(42,377)
Increase (decrease) in accounts payable and accrued expenses	117,010	(106,125)
Decrease in operating lease liabilities	(13,846)	(13,359)
Decrease in payable to PennyMac Mortgage Investment Trust	(35,099)	(127,710)
Increase in income taxes payable	20,395	62,664
Net cash provided by (used in) operating activities	237,269	(2,384,534)
Cash flow from investing activities
Decrease (increase) in short-term investment	358,325	(657,666)
Purchase of principal-only stripped mortgage-backed securities		(935,356)
Repayment of principal-only stripped mortgage-backed securities	119,258	36,506
Sale of interest-only stripped mortgage-backed securities		121,520
Net settlement of derivative financial instruments used for hedging of mortgage servicing rights	143,439	(210,157)
Sale of mortgage servicing rights to non-affiliates	165,162
Sale of mortgage servicing rights to PennyMac Mortgage Investment Trust	1,895
Acquisition of capitalized software	(24,484)	(13,001)
Purchase of furniture, fixtures, equipment and leasehold improvements	(3,751)	(1,467)
Increase in margin deposits	(133,835)	(99,989)
Net cash (provided by) used in investing activities	626,009	(1,759,610)
Cash flow from financing activities
Sale of assets under agreements to repurchase	101,562,221	77,065,706
Repurchase of assets sold under agreements to repurchase	(103,118,313)	(74,225,451)
Issuance of mortgage loan participation purchase and sale certificates	18,936,637	17,117,748
Repayment of mortgage loan participation purchase and sale certificates	(18,733,607)	(17,046,112)
Issuance of notes payable secured by mortgage servicing assets	525,000	725,000
Repayment of notes payable secured by mortgage servicing assets	(1,250,000)	(875,000)
Issuance of unsecured senior notes	2,350,000	650,000
Repayment of unsecured senior notes	(650,000)
Payment of debt issuance costs	(57,062)	(32,432)
Issuance of common stock by exercise of stock options	10,406	18,016
Payment of withholding taxes relating to stock-based compensation	(3,763)	(9,401)
Payment of dividends to holders of common stock	(46,619)	(36,487)
Repurchase of common stock	(4,739)
Net cash (used in) provided by financing activities	(479,839)	3,351,587
Net increase (decrease) in cash	383,439	(792,557)
Cash at beginning of quarter	238,482	938,371
Cash at end of quarter	621,921	145,814
Supplemental cash flow information:
Cash paid for interest	700,541	571,461
Cash paid for income taxes, net	2,371	2,064
Non-cash investing activities:
Mortgage servicing rights received from loan sales	2,165,213	1,532,709
Exchange of mortgage servicing spread for interest-only stripped mortgage-backed securities		121,520
Operating right-of-use assets recognized	13,622	1,388
Unsettled portion of MSR sales	18,352
Non-cash financing activities:
Issuance of common stock in settlement of directors' fees	$ 173	$ 199