Net Gains on Loans Held for Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Cash loss:
Loans	$ 605,559	$ (22,838)	$ 1,219,732	$ (77,659)
Hedging activities	(72,268)	(148,128)	(421,947)	(230,200)
Cash gain (loss), net of effects of cash hedging, on sale of loans held for sale	533,291	(170,966)	797,785	(307,859)
Non-cash gain:
Mortgage servicing rights and mortgage servicing liabilities resulting from loan sales	245,946	227,256	747,219	518,706
Provision for losses relating to representations and warranties on loans sold pursuant to loan sales	(5,219)	(2,508)	(13,120)	(5,222)
Provision for losses relating to representations and warranties on loans sold reduction in liability due to change in estimate	2,473	1,175	5,419	6,305
Change in fair value of loans and derivatives held at period end:
Interest rate lock commitments	173,381	33,347	404,795	95,785
Loans	(79,776)	(5,822)	(140,878)	(35,508)
Hedging derivatives	(5,052)	92,588	17,955	72,838
From non-affiliates	865,044	175,070	1,819,175	345,045
Recapture payable to PennyMac Mortgage Investment Trust	(9,775)	60,662	62,549	122,996
Net gains on loans held for sale at fair value	$ 855,269	$ 235,732	$ 1,881,724	$ 468,041