Regulatory Capital and Liquidity Requirements (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2015	Dec. 31, 2018
Fannie Mae / Freddie Mac - PLS
Regulatory Net Worth and Agency Capital Requirements
Net worth	$ 1,833,819,000		$ 1,788,430,000
Capital Requirement	561,020,000		514,089,000
Liquidity	287,089,000		271,802,000
Liquidity requirement	$ 77,292,000		$ 70,775,000
Tangible net worth / Total assets ratio actual	20.00%		21.00%
Tangible net worth / Total assets ratio requirement	6.00%		6.00%
Ginnie Mae - PLS
Regulatory Net Worth and Agency Capital Requirements
Net worth	$ 1,543,756,000		$ 1,535,826,000
Capital Requirement	819,028,000		733,342,000
Liquidity	287,089,000		271,802,000
Liquidity requirement	208,693,000		189,592,000
Ginnie Mae - PennyMac
Regulatory Net Worth and Agency Capital Requirements
Net worth	1,802,129,000		1,786,430,000
Capital Requirement	900,931,000		806,676,000
Ginnie Mae - PennyMac \| 1-4 unit servicing portfolio
Regulatory Net Worth and Agency Capital Requirements
Net worth	$ 2,500,000
FHFA net worth requirement spread	0.35%
FHFA liquidity spread of UPB serviced	0.10%
Liquidity requirement	$ 1,000,000
HUD - PLS
Regulatory Net Worth and Agency Capital Requirements
Net worth	1,543,756,000		1,535,826,000
Capital Requirement	$ 2,500,000		$ 2,500,000
Federal Housing Finance Agency
Regulatory Net Worth and Agency Capital Requirements
Net worth		$ 2,500,000
FHFA liquidity spread of UPB serviced		0.035%
FHFA additional liquidity spread of UPB in excess of 6%		$ 2
Federal Housing Finance Agency \| 1-4 unit servicing portfolio
Regulatory Net Worth and Agency Capital Requirements
FHFA net worth requirement spread		0.25%

The liquidity requirement additional spread of the total non-performing unpaid principal balance in excess of 6.0%.

No definition available.

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- Definition

The liquidity requirement spread of the aggregate unpaid principal balance serviced, required by the Federal Housing Finance Agency.

+ References

No definition available.

+ Details

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- Definition

The eligibility requirement spread added to the net worth requirement, as a percent of the Company's total servicing portfolio, required by the Federal Housing Finance Agency.

+ References

No definition available.

+ Details

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- Definition

The amount of total liquidity as defined in the regulations.

+ References

No definition available.

+ Details

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- Definition

The lowest amount of liquidity required by secondary market investors or state-imposed regulatory mandates.

+ References

No definition available.

+ Details

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- Definition

The tangible net worth to total assets ratio actual.

+ References

No definition available.

+ Details

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- Definition

The tangible net worth to total assets ratio requirement.

+ References

No definition available.

+ Details

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- Definition

The amount of total capital as defined in the regulations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

+ Details

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