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SCHEDULE VI SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS |  |  |
Current Accident Year | $ 649.2 | $ 712.9 | $ 732.0
Prior Accident Year | $ 14.8 | $ (4.0) | $ 92.0
Rate at which reserves are discounted (as a percent) | 2.50% | 2.50% | 2.50%
OneBeacon |  |  |
SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS |  |  |
Deferred acquisition costs | $ 96.3 | $ 100.7 | $ 103.2
Reserves for Unpaid Claims and Claims Adjustment Expenses | 1,365.6 | 1,389.8 | 1,342.2
Discount, if any, deducted in Column C | 1.6 | 1.1 | 1.0
Unearned Premiums | 575.1 | 560.3 | 588.3
Earned Premiums | 1,100.6 | 1,176.2 | 1,177.1
Net investment income | 50.6 | 45.9 | 43.4
Current Accident Year | 640.6 | 702.5 | 725.3
Prior Accident Year | 15.4 | (1.8) | 89.8
Amortization of deferred policy acquisition | (206.0) | (213.8) | (203.3)
Paid Claims and Claims Adjustment Expenses | 667.1 | 677.5 | 608.6
Premiums written | 1,100.7 | 1,136.6 | 1,216.9
Other Operations |  |  |
SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS |  |  |
Deferred acquisition costs | 0.0 | 0.0 | 0.0
Reserves for Unpaid Claims and Claims Adjustment Expenses | 5.0 | 6.0 | 7.8
Discount, if any, deducted in Column C | 0.0 | 0.0 | 0.0
Unearned Premiums | 1.2 | 2.1 | 0.8
Earned Premiums | 7.5 | 8.7 | 6.1
Net investment income | 0.2 | 0.2 | 0.2
Current Accident Year | 8.6 | 10.4 | 6.7
Prior Accident Year | (0.6) | (2.2) | 2.2
Amortization of deferred policy acquisition | 0.0 | 0.0 | 0.0
Paid Claims and Claims Adjustment Expenses | 8.8 | 10.4 | 14.8
Premiums written | $ 6.5 | $ 10.1 | $ 5.9

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- Definition Amount of amortization expense on deferred policy acquisition cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount of deferred policy acquisition cost related to property-casualty insurance policy written. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition The amount of discount that may be deducted from the reserve for unpaid claims and claims adjustment expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount of property-casualty insurance premium revenue earned on insurance policies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition The rate at which the discount was computed for each business segment reported. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount of net investment income earned by property-casualty insurance underwriter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Payments of claims and claims adjustment expenses during the period of a property-casualty insurance entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount of actual premium written by property-casualty insurance underwriter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition The amount of reserve, policy claim payable and loss expense incurred by property-casualty insurance underwriter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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- Definition Amount of property-casualty insurance premium revenue not yet earned on insurance policies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-18) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915 + Details
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