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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, 2015 | Dec. 31, 2014 | Dec. 31, 2013
SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS |  |  |
Current Accident Year | $ 712.9 | $ 732.0 | $ 622.1
Prior Accident Year | $ (4.0) | $ 92.0 | $ 0.0
Rate at which reserves are discounted (as a percent) | 2.50% | 2.50% | 3.50%
OneBeacon |  |  |
SUPPLEMENTAL INFORMATION FOR PROPERTY AND CASUALTY INSURANCE UNDERWRITERS |  |  |
Deferred acquisition costs | $ 100.7 | $ 103.2 | $ 103.7
Reserves for Unpaid Claims and Claims Adjustment Expenses | 1,389.8 | 1,342.2 | 1,054.3
Discount, if any, deducted in Column C | 1.1 | 1.0 | 3.0
Unearned Premiums | 560.3 | 588.3 | 544.9
Earned Premiums | 1,176.2 | 1,177.1 | 1,120.4
Net investment income | 45.9 | 43.4 | 43.0
Current Accident Year | 702.5 | 725.3 | 622.1
Prior Accident Year | (1.8) | 89.8 | 0.0
Amortization of deferred policy acquisition | (213.8) | (203.3) | (208.9)
Paid Claims and Claims Adjustment Expenses | 677.5 | 608.6 | 540.7
Premiums written | 1,136.6 | 1,216.9 | 1,088.6
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 | 6.0 | 7.8 | 0.0
Discount, if any, deducted in Column C | 0.0 | 0.0 | 0.0
Unearned Premiums | 2.1 | 0.8 | 0.0
Earned Premiums | 8.7 | 6.1 | 0.0
Net investment income | 0.2 | 0.2 | 0.0
Current Accident Year | 10.4 | 6.7 | 0.0
Prior Accident Year | (2.2) | 2.2 | 0.0
Amortization of deferred policy acquisition | 0.0 | 0.0 | 0.0
Paid Claims and Claims Adjustment Expenses | 10.4 | 14.8 | 0.0
Premiums written | $ 10.1 | $ 5.9 | $ 0.0

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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 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 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 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 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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