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SCHEDULE IV REINSURANCE | 12 Months Ended
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Dec. 31, 2017
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract] |
SCHEDULE IV REINSURANCE | WHITE MOUNTAINS INSURANCE GROUP, LTD. REINSURANCE (2)
Column A |  | Column B |  | Column C |  | Column D |  | Column E |  | Column F
$ in millions Premiums earned |  | Gross amount |  | Ceded to other companies |  | Assumed from other companies |  | Net amount |  | Percentage of amount assumed to net
Years ended: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
December 31, 2017 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | $ | 9.4 |  |  | $ | — |  |  | $ | — |  |  | $ | 9.4 |  |  | — | %
Other operations (1) |  | 1.0 |  |  | — |  |  | — |  |  | 1.0 |  |  | — |
December 31, 2016 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | 5.9 |  |  | — |  |  | — |  |  | 5.9 |  |  | — | %
Other operations (1) |  | 15.2 |  |  | (7.7 | ) |  | — |  |  | 7.5 |  |  | — |
December 31, 2015 |  |  |  |  |  |  |  |  |  |  |  |  |  |
HG Global/BAM |  | 3.3 |  |  | — |  |  | — |  |  | 3.3 |  |  | — | %
Other operations (1) |  | 20.7 |  |  | (12.0 | ) |  | $ | — |  |  | 8.7 |  |  | — | %
(1) | The Other operations amounts shown relate to SSIE. White Mountains completed the sale of SSIE on March 7, 2017. See Note 19 — “Held for Sale and Discontinued Operations”.
(2) | Schedule excludes activity related to OneBeacon and Sirius Group for all periods presented. See Note 19 — “Held for Sale and Discontinued Operations”.
Schedules of the Registrant should be read in conjunction with the Consolidated Financial Statements and Notes.

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- Definition The entire disclosure for the supplemental schedule of reinsurance information. Reinsurance schedule includes, but is not limited to, the type of insurance, gross amount of premiums, premiums ceded to other entities, premiums assumed from other entities, net amount of premium revenue, and the percentage of the premiums assumed to net premium revenue. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.7-05.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=6879921&loc=d3e569147-122900 + Details
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