XML 72 R55.htm IDEA: XBRL DOCUMENT
v3.3.1.900

Fair Value Measurement (Methodologies Other Than Fair Value) (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Financial assets: |  |
BOLI | $ 57,213 | $ 56,381
Other investments | 79,133 | 86,057
Other assets | 106,108 | 93,263
Financial liabilities: |  |
Debt | 350,000 | 250,000
Other liabilities | 202,303 | 320,853
Not Measured At Fair Value [Member] | Carrying Value [Member] |  |
Financial assets: |  |
BOLI | 57,213 | 56,381
Other investments | 48,522 | 57,099
Other assets | 24,215 | 22,440
Financial liabilities: |  |
Other liabilities | 14,897 | 14,656
Not Measured At Fair Value [Member] | Carrying Value [Member] | Senior notes due 2023 [Member] |  |
Financial liabilities: |  |
Debt | 250,000 | 250,000
Not Measured At Fair Value [Member] | Carrying Value [Member] | Revolving Credit Facility [Member] |  |
Financial liabilities: |  |
Debt | 100,000 | 0
Not Measured At Fair Value [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value [Member] |  |
Financial assets: |  |
BOLI | 57,213 | 56,381
Other investments | 51,646 | 57,994
Other assets | 24,193 | 22,399
Financial liabilities: |  |
Other liabilities | 14,893 | 14,645
Not Measured At Fair Value [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value [Member] | Senior notes due 2023 [Member] |  |
Financial liabilities: |  |
Debt | 261,308 | 276,503
Not Measured At Fair Value [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value [Member] | Revolving Credit Facility [Member] |  |
Financial liabilities: |  |
Debt | $ 100,000 | $ 0

X
- Definition Represents the aggregate of total long-term debt, including current maturities and short-term debt. + References No definition available. + Details
Name: | us-gaap_DebtLongtermAndShorttermCombinedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 30 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6384206&loc=d3e41899-111602 + Details
Name: | us-gaap_LifeInsuranceCorporateOrBankOwnedAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 10 -Article 7 + Details
Name: | us-gaap_OtherAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Other investments not otherwise specified in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(f,g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_OtherInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_OtherLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=pra_NotMeasuredAtFairValueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=pra_Seniornotesdue2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |