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SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Net investment income | $ 86.8 | $ 60.8 | $ 59.5
OneBeacon |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Deferred acquisition costs | 96.3 | 100.7 | 103.2
Future policy benefits, losses, claims and loss expenses | 1,365.6 | 1,389.8 | 1,342.2
Unearned premiums | 575.1 | 560.3 | 588.3
Other policy claims and benefits payable | 0.0 | 0.0 | 0.0
Premiums earned | 1,100.6 | 1,176.2 | 1,177.1
Net investment income | 50.6 | 45.9 | 43.4
Benefits, claims, losses, and settlement expenses | 656.0 | 700.7 | 815.1
Amortization of deferred policy acquisition costs | 206.0 | 213.8 | 203.3
Other operating expenses | 209.0 | 218.2 | 179.2
Premiums written | 1,100.7 | 1,136.6 | 1,216.9
Net investment income | 50.6 | 45.9 | 43.4
HG Global-BAM |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Deferred acquisition costs | 10.6 | 6.9 | 4.0
Future policy benefits, losses, claims and loss expenses | 0.0 | 0.0 | 0.0
Unearned premiums | 82.9 | 50.2 | 27.6
Other policy claims and benefits payable | 0.0 | 0.0 | 0.0
Premiums earned | 5.9 | 3.3 | 1.8
Net investment income | 9.0 | 6.1 | 7.1
Benefits, claims, losses, and settlement expenses | 0.0 | 0.0 | 0.0
Amortization of deferred policy acquisition costs | 3.4 | 2.9 | 2.1
Other operating expenses | 0.4 | 0.4 | 0.4
Premiums written | 38.6 | 25.9 | 16.2
Other Operations |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Deferred acquisition costs | 0.0 | 0.0 | 0.0
Future policy benefits, losses, claims and loss expenses | 5.0 | 6.0 | 7.8
Unearned premiums | 1.2 | 2.1 | 0.8
Other policy claims and benefits payable | 0.0 | 0.0 | 0.0
Premiums earned | 7.5 | 8.7 | 6.1
Net investment income | 0.2 | 0.2 | 0.2
Benefits, claims, losses, and settlement expenses | 8.0 | 8.2 | 8.9
Amortization of deferred policy acquisition costs | 2.2 | 3.4 | 0.8
Other operating expenses | 0.1 | 0.0 | 0.0
Premiums written | 6.5 | 10.1 | 5.9
Non-insurance [Member] | Operating Segments |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Net investment income | $ 27.0 | $ 8.6 | $ 8.8

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- 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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -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 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16(Column G)) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915 + Details
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- Definition Amount of insurance benefits, claims, losses and settlement expenses incurred. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915 + Details
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- Definition Net amount of deferred policy acquisition costs capitalized on contracts remaining in force on the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915 + Details
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- Definition Amount of reserves for future policy claims payable and loss expenses to be incurred. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915 + Details
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