Third Party Reinsurance

6 Months Ended

Jun. 30, 2015

Reinsurance Disclosures [Abstract]

Third Party Reinsurance

Third Party Reinsurance

In the normal course of business, White Mountains’s insurance and reinsurance subsidiaries may seek to limit losses that may arise from catastrophes or other events by reinsuring with third party reinsurers. White Mountains remains liable for risks reinsured in the event that the reinsurer does not honor its obligations under reinsurance contracts.

OneBeacon

At June 30, 2015, OneBeacon had $20.9 million and $147.1 million of reinsurance recoverables on paid and unpaid losses. At December 31, 2014, OneBeacon had $12.2 million and $161.6 million of reinsurance recoverables on paid and unpaid losses. The reinsurance balances associated with the Runoff Business are included in discontinued operations. (See Note 17 - “Discontinued Operations”). Reinsurance contracts do not relieve OneBeacon of its obligation to its policyholders. OneBeacon is selective with its reinsurers, placing reinsurance with only those reinsurers having a strong financial condition. OneBeacon monitors the financial strength and ratings of its reinsurers on an ongoing basis. Uncollectible amounts related to the ongoing specialty business historically have not been significant.

Except as discussed below, there have been no material changes to OneBeacon's reinsurance coverage as discussed in Note 4 —“Reinsurance”in White Mountains’s 2014 Annual Report on Form 10-K.

Effective January 1, 2015, OneBeacon purchased an aggregate stop loss on its multiple peril crop insurance (“MPCI”) portfolio, providing 52.0% coverage in excess of a 98.0% loss ratio on premiums covered by the contract and a separate aggregate stop loss providing 80% coverage in excess of a 100% loss ratio on its crop-hail portfolio. OneBeacon also purchased a new quota share contract on 30% of its MPCI portfolio.

Effective May 1, 2015, OneBeacon renewed its property catastrophe reinsurance program through April 30, 2016. The program provides coverage for OneBeacon's property business as well as certain acts of terrorism. Under the program, the first $20.0 million of losses resulting from any single catastrophe are retained, and 95.0% of the next $10.0 million of losses and 100.0% of the next $100.0 million of losses resulting from the catastrophe are reinsured. The part of the catastrophe loss in excess of $130.0 million would be retained in full. In the event of a catastrophe, OneBeacon's property catastrophe reinsurance program is reinstated for the remainder of the original contract term by paying a reinstatement premium that is based on the percentage of coverage reinstated and the original property catastrophe coverage premium.

Also effective May 1, 2015, OneBeacon lowered its retention on its property-per-risk reinsurance program from $5.0 million to $3.0 million.

Effective June 1, 2015, OneBeacon lowered its retentions on certain casualty and healthcare treaties from $5.0 million to $3.0 million.

Sirius Group

At June 30, 2015, Sirius Group had $10.8 million and $280.3 million of reinsurance recoverables on paid and unpaid losses that will become recoverable if claims are paid in accordance with current reserve estimates. At December 31, 2014, Sirius Group had $11.4 million and $322.2 million of reinsurance recoverables on paid and unpaid losses. Because retrocessional reinsurance contracts do not relieve Sirius Group of its obligation to its insureds, the collectability of balances due from Sirius Group’s reinsurers is important to its financial strength. Sirius Group monitors the financial strength and ratings of retrocessionaires on an ongoing basis. Uncollectible amounts historically have not been significant.

In connection with the sale of Sirius Group, White Mountains caused Sirius Group to purchase several industry loss warranty (“ILW”) contracts to augment its overall retrocessional program in order to reduce the risk of loss from major catastrophes subsequent to the signing of the definitive agreement to sell Sirius Group. (See Note 19 - “Subsequent Events”).