XML 92 R79.htm IDEA: XBRL DOCUMENT
v3.21.2

Segment Information (Financial Data by Segment) (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
May 05, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | $ 272,248 | $ 194,559 | $ 698,598 | $ 605,708 |
Net investment income |  | 19,278 | 16,924 | 51,713 | 55,877 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 15,244 | 4,853 | 33,959 | (22,065) |
Net realized gains (losses) |  | 530 | 8,838 | 20,212 | 150 |
Other income (loss) (expense) |  | 2,400 | 1,723 | 6,862 | 5,668 |
Net losses and loss adjustment expenses |  | (223,393) | (145,581) | (555,030) | (521,412) |
Underwriting, policy acquisition and operating expenses |  | (64,485) | (59,433) | (176,915) | (180,178) |
SPC U.S. federal income taxes expense |  | (431) | (871) | (1,291) | (1,573) |
SPC dividend (expense) income |  | (1,320) | (3,854) | (5,926) | (7,988) |
Interest expense |  | (5,814) | (3,881) | (14,203) | (11,725) |
Income tax benefit (expense) |  | (219) | (2,141) | (1,369) | 48,621 |
Segment results |  | 14,038 | 11,136 | 56,610 | (28,917) |
Gain on bargain purchase |  | 0 | 0 | 74,408 | 0 |
Goodwill impairment |  | 0 | 161,115 | 0 | 161,115 | $ 161,115
Net income (loss) |  | 12,200 | (149,979) | 111,984 | (190,032) |
Depreciation and amortization, net of accretion |  | 10,246 | 6,345 | 26,566 | 16,168 |
Income tax expense (benefit) |  | (270) | 2,141 | (3,132) | (48,621) |
NORCAL Group |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Gain on bargain purchase | $ 74,408 |  |  |  |  |
Transaction-related costs |  | (2,300) | (500) | (23,500) | (1,600) |
Income tax expense (benefit) |  | (500) |  | (4,500) |  |
Specialty P&C |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 203,716 | 117,849 | 487,963 | 365,305 |
Workers' Compensation Insurance |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 42,235 | 42,516 | 122,872 | 129,437 |
Segregated Portfolio Cell Reinsurance |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 15,344 | 16,052 | 47,500 | 49,780 |
Lloyd's Syndicates |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 10,953 | 18,142 | 40,263 | 61,186 |
Operating segments | Specialty P&C |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 203,716 | 117,849 | 487,963 | 365,305 |
Net investment income |  | 0 | 0 | 0 | 0 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 0 | 0 | 0 | 0 |
Net realized gains (losses) |  | 0 | 0 | 0 | 0 |
Other income (loss) (expense) |  | 860 | 726 | 2,800 | 3,515 |
Net losses and loss adjustment expenses |  | (176,490) | (102,951) | (417,890) | (373,442) |
Underwriting, policy acquisition and operating expenses |  | (36,147) | (28,074) | (91,369) | (82,894) |
SPC U.S. federal income taxes expense |  | 0 | 0 | 0 | 0 |
SPC dividend (expense) income |  | 0 | 0 | 0 | 0 |
Interest expense |  | 0 | 0 | 0 | 0 |
Income tax benefit (expense) |  | 0 | 0 | 0 | 0 |
Segment results |  | (8,061) | (12,450) | (18,496) | (87,516) |
Depreciation and amortization, net of accretion |  | 1,956 | 2,669 | 7,261 | 5,930 |
Operating segments | Workers' Compensation Insurance |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 42,235 | 42,516 | 122,872 | 129,437 |
Net investment income |  | 0 | 0 | 0 | 0 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 0 | 0 | 0 | 0 |
Net realized gains (losses) |  | 0 | 0 | 0 | 0 |
Other income (loss) (expense) |  | 437 | 441 | 1,730 | 1,717 |
Net losses and loss adjustment expenses |  | (31,364) | (26,455) | (85,323) | (84,648) |
Underwriting, policy acquisition and operating expenses |  | (13,521) | (14,983) | (38,519) | (42,604) |
SPC U.S. federal income taxes expense |  | 0 | 0 | 0 | 0 |
SPC dividend (expense) income |  | 0 | 0 | 0 | 0 |
Interest expense |  | 0 | 0 | 0 | 0 |
Income tax benefit (expense) |  | 0 | 0 | 0 | 0 |
Segment results |  | (2,213) | 1,519 | 760 | 3,902 |
Depreciation and amortization, net of accretion |  | 903 | 923 | 2,709 | 2,771 |
Operating segments | Segregated Portfolio Cell Reinsurance |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 15,344 | 16,052 | 47,500 | 49,780 |
Net investment income |  | 193 | 273 | 620 | 832 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 0 | 0 | 0 | 0 |
Net realized gains (losses) |  | 204 | 1,495 | 2,772 | 894 |
Other income (loss) (expense) |  | 0 | 12 | 2 | 203 |
Net losses and loss adjustment expenses |  | (8,693) | (6,858) | (26,560) | (23,890) |
Underwriting, policy acquisition and operating expenses |  | (4,758) | (5,036) | (15,078) | (15,474) |
SPC U.S. federal income taxes expense |  | (431) | (871) | (1,291) | (1,573) |
SPC dividend (expense) income |  | (1,320) | (3,854) | (5,926) | (7,988) |
Interest expense |  | 0 | 0 | 0 | 0 |
Income tax benefit (expense) |  | 0 | 0 | 0 | 0 |
Segment results |  | 539 | 1,213 | 2,039 | 2,784 |
Depreciation and amortization, net of accretion |  | 397 | 210 | 1,074 | 371 |
Operating segments | Lloyd's Syndicates |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 10,953 | 18,142 | 40,263 | 61,186 |
Net investment income |  | 431 | 951 | 1,677 | 3,236 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 0 | 0 | 0 | 0 |
Net realized gains (losses) |  | 35 | 489 | 9 | 1,100 |
Other income (loss) (expense) |  | 283 | 411 | 864 | 219 |
Net losses and loss adjustment expenses |  | (6,846) | (9,317) | (25,257) | (39,432) |
Underwriting, policy acquisition and operating expenses |  | (3,909) | (6,938) | (15,219) | (23,373) |
SPC U.S. federal income taxes expense |  | 0 | 0 | 0 | 0 |
SPC dividend (expense) income |  | 0 | 0 | 0 | 0 |
Interest expense |  | 0 | 0 | 0 | 0 |
Income tax benefit (expense) |  | 0 | 0 | 0 | 29 |
Segment results |  | 947 | 3,738 | 2,337 | 2,965 |
Depreciation and amortization, net of accretion |  | 17 | 3 | 49 | 26 |
Operating segments | Corporate |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 0 | 0 | 0 | 0 |
Net investment income |  | 18,654 | 15,700 | 49,416 | 51,809 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 15,244 | 4,853 | 33,959 | (22,065) |
Net realized gains (losses) |  | 291 | 6,854 | 17,431 | (1,844) |
Other income (loss) (expense) |  | 1,542 | 775 | 3,786 | 1,813 |
Net losses and loss adjustment expenses |  | 0 | 0 | 0 | 0 |
Underwriting, policy acquisition and operating expenses |  | (6,872) | (5,044) | (19,050) | (17,632) |
SPC U.S. federal income taxes expense |  | 0 | 0 | 0 | 0 |
SPC dividend (expense) income |  | 0 | 0 | 0 | 0 |
Interest expense |  | (5,814) | (3,881) | (14,203) | (11,725) |
Income tax benefit (expense) |  | (219) | (2,141) | (1,369) | 48,592 |
Segment results |  | 22,826 | 17,116 | 69,970 | 48,948 |
Depreciation and amortization, net of accretion |  | 6,973 | 2,540 | 15,473 | 7,070 |
Inter-segment Eliminations |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Net premiums earned |  | 0 | 0 | 0 | 0 |
Net investment income |  | 0 | 0 | 0 | 0 |
Equity in earnings (loss) of unconsolidated subsidiaries |  | 0 | 0 | 0 | 0 |
Net realized gains (losses) |  | 0 | 0 | 0 | 0 |
Other income (loss) (expense) |  | (722) | (642) | (2,320) | (1,799) |
Net losses and loss adjustment expenses |  | 0 | 0 | 0 | 0 |
Underwriting, policy acquisition and operating expenses |  | 722 | 642 | 2,320 | 1,799 |
SPC U.S. federal income taxes expense |  | 0 | 0 | 0 | 0 |
SPC dividend (expense) income |  | 0 | 0 | 0 | 0 |
Interest expense |  | 0 | 0 | 0 | 0 |
Income tax benefit (expense) |  | 0 | 0 | 0 | 0 |
Segment results |  | 0 | 0 | 0 | 0 |
Depreciation and amortization, net of accretion |  | 0 | 0 | 0 | 0 |
Segment reconciling items |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Gain on bargain purchase |  |  |  | 74,408 |  |
Transaction-related costs |  | $ (1,838) |  | $ (19,034) |  |
Goodwill impairment |  |  | $ 161,115 |  | $ 161,115 |

X
- Definition Equity In Earnings (Loss) Of Unconsolidated Subsidiaries + References No definition available. + Details
Name: | pra_EquityInEarningsLossOfUnconsolidatedSubsidiaries
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Income Tax Expense (Benefit), Excluding Business Acquisition Tax Effect + References No definition available. + Details
Name: | pra_IncomeTaxExpenseBenefitExcludingBusinessAcquisitionTaxEffect
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Segment Profit (Loss) + References No definition available. + Details
Name: | pra_SegmentProfitLoss
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Segregated Portfolio Cells Dividend Expense (Income) + References No definition available. + Details
Name: | pra_SegregatedPortfolioCellsDividendExpenseIncome
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Segregated Portfolio Cells Income Tax Expense (Benefit) + References No definition available. + Details
Name: | pra_SegregatedPortfolioCellsIncomeTaxExpenseBenefit
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Underwriting, policy acquisition and operating expense. + References No definition available. + Details
Name: | pra_UnderwritingPolicyAcquisitionAndOperatingExpense
Namespace Prefix: | pra_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460 + Details
Name: | us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6571-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6387-128476 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6396-128476 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6527-128477 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 25 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6393-128476 + Details
Name: | us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
Name: | us-gaap_DepreciationAmortizationAndAccretionNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of realized and unrealized gain (loss) on investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27405-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
Name: | us-gaap_GainLossOnInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13777-109266 + Details
Name: | us-gaap_GoodwillImpairmentLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32672-109319 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22663-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123586238&loc=d3e38679-109324 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(9)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22658-107794 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the cost of borrowed funds accounted for as interest expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (210.5-03(11)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_InterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123482062&loc=SL123482106-238011 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=124431353&loc=SL124452729-227067 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(5)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iv)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iii)(A)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(i)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(i)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22663-107794 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iv)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756 Reference 17: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(ii)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=125511455&loc=SL5780133-109256 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22658-107794 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669619-108580 Reference 25: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8924-108599 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794 Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794 Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669625-108580 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(5)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756 Reference 32: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(B)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756 Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(A)) -URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756 Reference 34: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599 Reference 35: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
Name: | us-gaap_NetInvestmentIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of revenue and income classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.4) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
Name: | us-gaap_OtherIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.5) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387 + Details
Name: | us-gaap_PolicyholderBenefitsAndClaimsIncurredNet
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 premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column E)) -URI http://asc.fasb.org/extlink&oid=120401096&loc=d3e574992-122915 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(c)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 + Details
Name: | us-gaap_PremiumsEarnedNet
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_BusinessAcquisitionAxis=pra_NORCALGroupMember
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_StatementBusinessSegmentsAxis=pra_WorkersCompensationInsuranceSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=pra_SegregatedPortfolioCellReinsuranceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=pra_LloydsSyndicatesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=us-gaap_CorporateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_MaterialReconcilingItemsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |