Transactions with Affiliates - Financing Activities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 19, 2016
PMT
Financing activities:
Issuance pursuant to recapture agreement	$ 1,757,000	$ 2,688,000	$ 5,244,000
Repayments	40,316,000	46,750,000	54,980,000
interest expense	10,291,000	15,138,000	16,951,000
Excess servicing spread financing at fair value payable to affiliate	178,586,000	216,110,000
PMT | 2/1/13 Spread Acquisition Agreement
Financing activities:
Maximum ESS recapture obligation				$ 200,000
Excess servicing spread financing
Financing activities:
Gain (loss) recognized	(9,256,000)	8,500,000	(19,350,000)
Excess servicing spread financing | PMT
Financing activities:
Issuance pursuant to recapture agreement	1,757,000	2,688,000	5,244,000
Repayments	40,316,000	46,750,000	54,980,000
Gain (loss) recognized	9,256,000	(8,500,000)	19,350,000
interest expense	10,291,000	15,138,000	16,951,000
Excess servicing spread recapture recognized	1,726,000	2,584,000	$ 4,820,000
Excess servicing spread financing at fair value payable to affiliate	$ 178,586,000	$ 216,110,000