The amount of increase (decrease) in additional paid in capital during the period.

No definition available.

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Namespace Prefix:	plmr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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Subsequent Events (Details) $ in Millions		1 Months Ended	3 Months Ended
Subsequent Events (Details) $ in Millions	Mar. 15, 2019	Mar. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)
Subsequent Events
One-time cash distribution		$ 5.1
Forward stock split	17,000,000
Subsequent Event
Subsequent Events
One-time cash distribution		$ 5.1
Forward stock split	17,000,000
2014 Management Incentive Plan \| Subsequent Event
Subsequent Events
Increase in additional paid-in capital			$ 23.0