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Third Party Reinsurance (Tables) | 12 Months Ended
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Dec. 31, 2015
Ceded Credit Risk [Line Items] |
Schedule of direct assumed and ceded amounts | The effects of reinsurance on White Mountains’s insurance and reinsurance subsidiaries’ written and earned premiums and on losses and LAE were as follows (see Note 10 - “Municipal Bond Guarantee Insurance” for balances related to White Mountains financial guarantee business):
|  | Year ended December 31, 2015
Millions |  | OneBeacon |  | HG/BAM (1) |  | Other |  | Total
Written premiums: |  |  |  |  |  |  |  |
Direct |  | $ | 1,279.9 |  |  | $ | 25.9 |  |  | $ | 19.9 |  |  | $ | 1,325.7 |
Assumed |  | 36.0 |  |  | — |  |  | — |  |  | 36.0 |
Gross written premiums |  | 1,315.9 |  |  | 25.9 |  |  | 19.9 |  |  | 1,361.7 |
Ceded |  | (179.3 | ) | (2) | — |  |  | (9.8 | ) |  | (189.1 | )
Net written premiums |  | $ | 1,136.6 |  |  | $ | 25.9 |  |  | $ | 10.1 |  |  | $ | 1,172.6 |
Earned premiums: |  |  |  |  |  |  |  |
Direct |  | $ | 1,298.0 |  |  | $ | 3.3 |  |  | $ | 20.7 |  |  | $ | 1,322.0 |
Assumed |  | 45.9 |  |  | — |  |  | — |  |  | 45.9 |
Gross earned premiums |  | 1,343.9 |  |  | 3.3 |  |  | 20.7 |  |  | 1,367.9 |
Ceded |  | (167.7 | ) | (2) | — |  |  | (12.0 | ) |  | (179.7 | )
Net earned premiums |  | $ | 1,176.2 |  |  | 3.3 |  |  | $ | 8.7 |  |  | $ | 1,188.2 |
Losses and LAE: |  |  |  |  |  |  |  |
Direct |  | $ | 783.0 |  |  | $ | — |  |  | $ | 19.5 |  |  | $ | 802.5 |
Assumed |  | 55.7 |  |  | — |  |  | — |  |  | 55.7 |
Gross losses and LAE |  | 838.7 |  |  | — |  |  | 19.5 |  |  | 858.2 |
Ceded |  | (138.0 | ) | (2) | — |  |  | (11.3 | ) |  | (149.3 | )
Net losses and LAE |  | $ | 700.7 |  |  | $ | — |  |  | $ | 8.2 |  |  | $ | 708.9 |
(1) During 2015, BAM ceded $19.3 in written premiums and $16.0 in earned premiums to HG Global, which have been eliminated within the HG/BAM segment. (2) During 2015, OneBeacon recorded ceded $33.3 in written premiums, $33.3 in earned premiums and $33.4 in loss and loss adjustment expenses as a result of the exit of the Crop Business due to the 100% quota share reinsurance agreement with AmTrust.
|  | Year ended December 31, 2014
Millions |  | OneBeacon |  | HG/BAM (1) |  | Other (2) |  | Total
Written premiums: |  |  |  |  |  |  |  |
Direct |  | $ | 1,257.5 |  |  | $ | 16.2 |  |  | $ | 22.6 |  |  | $ | 1,296.3 |
Assumed |  | 65.9 |  |  | — |  |  | — |  |  | 65.9 |
Gross written premiums |  | 1,323.4 |  |  | 16.2 |  |  | 22.6 |  |  | 1,362.2 |
Ceded |  | (106.5 | ) |  | — |  |  | (16.7 | ) |  | (123.2 | )
Net written premiums |  | $ | 1,216.9 |  |  | $ | 16.2 |  |  | $ | 5.9 |  |  | $ | 1,239.0 |
Earned premiums: |  |  |  |  |  |  |  |  |  |
Direct |  | $ | 1,209.1 |  |  | $ | 1.8 |  |  | $ | 22.6 |  |  | $ | 1,233.5 |
Assumed |  | 70.9 |  |  | — |  |  | — |  |  | 70.9 |
Gross earned premiums |  | 1,280.0 |  |  | 1.8 |  |  | 22.6 |  |  | 1,304.4 |
Ceded |  | (102.9 | ) |  | — |  |  | (16.5 | ) |  | (119.4 | )
Net earned premiums |  | $ | 1,177.1 |  |  | 1.8 |  |  | $ | 6.1 |  |  | $ | 1,185.0 |
Losses and LAE: |  |  |  |  |  |  |  |  |  |
Direct |  | $ | 778.7 |  |  | $ | — |  |  | $ | 24.1 |  |  | $ | 802.8 |
Assumed |  | 115.7 |  |  | — |  |  | — |  |  | 115.7 |
Gross losses and LAE |  | 894.4 |  |  | — |  |  | 24.1 |  |  | 918.5 |
Ceded |  | (79.3 | ) |  | — |  |  | (15.2 | ) |  | (94.5 | )
Net losses and LAE |  | $ | 815.1 |  |  | $ | — |  |  | $ | 8.9 |  |  | $ | 824.0 |
(1) During 2014, BAM ceded $12.3 in written premiums and $1.4 in earned premiums to HG Global, which have been eliminated within the HG/BAM segment. (2) During 2014, SSIE ceded $16.0 in written premiums, $15.7 in earned premiums, and $16.9 in loss and loss adjustment expenses to OneBeacon, which have been eliminated in consolidation.
|  | Year ended December 31, 2013
Millions |  | OneBeacon |  | HG/BAM (1) |  | Total
Written premiums: |  |  |  |  |  |
Direct |  | $ | 1,103.1 |  |  | $ | 13.6 |  |  | $ | 1,116.7 |
Assumed |  | 59.8 |  |  | — |  |  | 59.8 |
Gross written premiums |  | 1,162.9 |  |  | 13.6 |  |  | 1,176.5 |
Ceded |  | (74.3 | ) |  | — |  |  | (74.3 | )
Net written premiums |  | $ | 1,088.6 |  |  | $ | 13.6 |  |  | $ | 1,102.2 |
Earned premiums: |  |  |  |  |  |
Direct |  | $ | 1,043.3 |  |  | $ | .5 |  |  | $ | 1,043.8 |
Assumed |  | 148.5 |  |  | — |  |  | 148.5 |
Gross earned premiums |  | 1,191.8 |  |  | .5 |  |  | 1,192.3 |
Ceded |  | (71.4 | ) |  | — |  |  | (71.4 | )
Net earned premiums |  | $ | 1,120.4 |  |  | $ | .5 |  |  | $ | 1,120.9 |
Losses and LAE: |  |  |  |  |  |
Direct |  | $ | 584.9 |  |  | $ | — |  |  | $ | 584.9 |
Assumed |  | 76.3 |  |  | — |  |  | 76.3 |
Gross losses and LAE |  | 661.2 |  |  | — |  |  | 661.2 |
Ceded |  | (39.1 | ) |  | — |  |  | (39.1 | )
Net losses and LAE |  | $ | 622.1 |  |  | $ | — |  |  | $ | 622.1 |
(1) During 2013, BAM ceded $10.6 in written premiums ($10.2 in earned premiums) to HG Global, which have been eliminated within the HG/BAM segment.
OneBeacon |
Ceded Credit Risk [Line Items] |
Ceded Credit Risk | The following table summarizes Standard & Poor’s Financial Services LLC (“Standard & Poor’s”) ratings for OneBeacon’s reinsurers.
Standard & Poor’s Rating(1) |  |  |  |
$ in millions |  | Balance at December 31, 2015 |  | % of Total
AA |  | $ | 41.7 |  |  | 22 | %
A |  | 126.2 |  |  | 65 | %
BBB, Not rated and other (2) |  | 25.6 |  |  | 13 | %
Total |  | $ | 193.5 |  |  | 100 | %
(1) Standard & Poor’s ratings as detailed above are: “AA” (Very strong), “A” (Strong) and “BBB” (Adequate). (2) Includes $20.4 related to OBIC, an unrated entity sold to Armour as part of the Runoff Transaction.

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