Segments (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Segments and Related Information
Number of segments | item	3
Revenues:
Net gains on loans held for sale at fair value	$ 791,633	$ 2,464,401	$ 2,740,785
Loan origination fees	169,859	384,154	285,551
Fulfillment fees from PennyMac Mortgage Investment Trust	67,991	178,927	222,200
Net loan servicing fees	951,329	182,954	439,448
Net interest income (expense):
Interest income	294,062	300,169	247,026
Interest expense, before non-segment activities	335,427	390,699	271,551
Net interest expense, before non-segment activities	(41,365)	(90,530)	(24,525)
Management fees from PennyMac Mortgage Investment Trust	31,065	37,801	34,538
Other	15,243	9,654	7,600
Total net revenues, before non-segment activities	1,985,755	3,167,361	3,705,597
Expenses	1,320,508	1,808,178	1,464,988
Income (loss) before provision for income taxes and non-segment activities		1,359,183	2,240,609
Income before provision for income taxes	665,247	1,359,183	2,240,609
Assets:
Segment assets at quarter end	16,822,584	18,776,612
PennyMac Mortgage Investment Trust
Revenues:
Net gains on loans held for sale at fair value	(16,564)	(51,473)	50,681
Fulfillment fees from PennyMac Mortgage Investment Trust	$ 67,991	178,927	222,200
Net interest income (expense):
Interest income		387	3,325
Mortgage banking
Segments and Related Information
Number of segments | item	2
Operating segment
Assets:
Segment assets at quarter end	$ 16,822,584	18,776,612	31,597,795
Operating segment | Investment management
Net interest income (expense):
Interest expense, before non-segment activities		10	23
Net interest expense, before non-segment activities		(10)	(23)
Management fees from PennyMac Mortgage Investment Trust	31,065	37,801	34,538
Other	9,013	5,511	5,321
Total net revenues, before non-segment activities	40,078	43,302	39,836
Expenses	36,937	35,208	25,492
Income (loss) before provision for income taxes and non-segment activities		8,094	14,344
Income before provision for income taxes	3,141
Assets:
Segment assets at quarter end	26,417	21,144	18,275
Operating segment | Mortgage banking
Revenues:
Net gains on loans held for sale at fair value	791,633	2,464,401	2,740,785
Loan origination fees	169,859	384,154	285,551
Net loan servicing fees	951,329	182,954	439,448
Net interest income (expense):
Interest income	294,062	300,169	247,026
Interest expense, before non-segment activities	335,427	390,689	271,528
Net interest expense, before non-segment activities	(41,365)	(90,520)	(24,502)
Other	6,230	4,143	2,279
Total net revenues, before non-segment activities	1,945,677	3,124,059	3,665,761
Expenses	1,283,571	1,772,970	1,439,496
Income (loss) before provision for income taxes and non-segment activities		1,351,089	2,226,265
Income before provision for income taxes	662,106
Assets:
Segment assets at quarter end	16,796,167	18,755,468	31,579,520
Operating segment | Mortgage banking | PennyMac Mortgage Investment Trust
Revenues:
Fulfillment fees from PennyMac Mortgage Investment Trust	67,991	178,927	222,200
Operating segment | Mortgage banking Production
Revenues:
Net gains on loans held for sale at fair value	599,896	1,746,650	2,297,108
Loan origination fees	169,859	384,154	285,551
Net interest income (expense):
Interest income	133,000	134,706	101,605
Interest expense, before non-segment activities	108,072	139,296	82,160
Net interest expense, before non-segment activities	24,928	(4,590)	19,445
Other	2,503	1,623	695
Total net revenues, before non-segment activities	865,177	2,306,764	2,824,999
Expenses	816,697	1,262,353	860,878
Income (loss) before provision for income taxes and non-segment activities		1,044,411	1,964,121
Income before provision for income taxes	48,480
Assets:
Segment assets at quarter end	3,866,934	8,934,032	7,870,398
Operating segment | Mortgage banking Production | PennyMac Mortgage Investment Trust
Revenues:
Fulfillment fees from PennyMac Mortgage Investment Trust	67,991	178,927	222,200
Operating segment | Mortgage banking Servicing
Revenues:
Net gains on loans held for sale at fair value	191,737	717,751	443,677
Net loan servicing fees	951,329	182,954	439,448
Net interest income (expense):
Interest income	161,062	165,463	145,421
Interest expense, before non-segment activities	227,355	251,393	189,368
Net interest expense, before non-segment activities	(66,293)	(85,930)	(43,947)
Other	3,727	2,520	1,584
Total net revenues, before non-segment activities	1,080,500	817,295	840,762
Expenses	466,874	510,617	578,618
Income (loss) before provision for income taxes and non-segment activities		306,678	262,144
Income before provision for income taxes	613,626
Assets:
Segment assets at quarter end	$ 12,929,233	$ 9,821,436	$ 23,709,122