XML 69 R56.htm IDEA: XBRL DOCUMENT v3.7.0.1

Segment Information (Gross Premiums Earned by Product and Reconciliation to Net Premiums) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Net premiums earned	$ 180,353	$ 176,732	$ 363,256	$ 354,312
Operating Segments [Member] | Specialty P&C [Member]
Segment Reporting Information [Line Items]
Ceded premiums earned	(21,683)	(18,702)	(40,407)	(37,127)
Net premiums earned	109,005	108,126	222,063	218,882
Operating Segments [Member] | Specialty P&C [Member] | Healthcare professional liability [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	115,781	111,938	232,832	225,687
Operating Segments [Member] | Specialty P&C [Member] | Legal professional liability [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	6,417	6,493	12,734	13,107
Operating Segments [Member] | Specialty P&C [Member] | Medical technology and life sciences product liability [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	8,389	8,243	16,701	16,794
Operating Segments [Member] | Specialty P&C [Member] | Other [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	101	154	203	421
Operating Segments [Member] | Workers Compensation [Member]
Segment Reporting Information [Line Items]
Ceded premiums earned	(5,856)	(5,905)	(11,787)	(12,467)
Net premiums earned	56,854	55,093	112,137	109,476
Operating Segments [Member] | Workers Compensation [Member] | Traditional business [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	42,501	42,193	84,269	84,844
Operating Segments [Member] | Workers Compensation [Member] | Alternative market business [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	20,209	18,805	39,655	37,099
Operating Segments [Member] | Lloyds Syndicate [Member]
Segment Reporting Information [Line Items]
Ceded premiums earned	(2,466)	(346)	(5,089)	(1,277)
Net premiums earned	14,494	13,513	29,056	25,954
Operating Segments [Member] | Lloyds Syndicate [Member] | Property, Liability and Casualty Insurance Product Line [Member]
Segment Reporting Information [Line Items]
Gross premiums earned	$ 16,960	$ 13,859	$ 34,145	$ 27,231

X

- Definition

Amount of premiums earned before premiums ceded to other entities, including directed and assumed premiums earned.

+ References

No definition available.

+ Details

Name:	pra_GrossPremiumsEarned
Namespace Prefix:	pra_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of earned premiums ceded to other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.1)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (b),(c)(2)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486662&loc=d3e27175-158546

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

+ Details

Name:	us-gaap_CededPremiumsEarned
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of property and casualty premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.1)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
-Paragraph 1
-Subparagraph (b),(c)
-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486662&loc=d3e27175-158546

+ Details

Name:	us-gaap_PremiumsEarnedNetPropertyAndCasualty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- 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.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=pra_SpecialtyPropertyandCasualtyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_HealthcareProfessionalLiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_LegalProfessionalLiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_MedicalTechnologyandLifeSciencesProductLiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_OtherPremiumsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=pra_WorkersCompensationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_WorkersCompensationTraditionalBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=pra_WorkersCompensationAlternativeMarketBusinessMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=pra_LloydsSyndicateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ProductOrServiceAxis=us-gaap_PropertyLiabilityAndCasualtyInsuranceSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: