XML 79 R39.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Income Taxes (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2019
Income Tax Disclosure [Abstract] |
Schedule of total income tax benefit (expense) | The following table presents the total income tax (expense) benefit for the years ended December 31, 2019, 2018 and 2017:
|  | Year Ended December 31,
Millions |  | 2019 |  | 2018 |  | 2017
Current income tax benefit (expense): |  |  |  |  |  |  |  |  |
U.S. federal |  | $ | .9 |  |  | $ | (.1 | ) |  | $ | (.3 | )
State |  | (3.7 | ) |  | (1.4 | ) |  | (1.3 | )
Non-U.S. |  | (1.7 | ) |  | (2.9 | ) |  | (2.0 | )
Total current income tax (expense) benefit |  | (4.5 | ) |  | (4.4 | ) |  | (3.6 | )
Deferred income tax (expense) benefit: |  |  |  |  |  |  |  |  |
U.S. federal |  | (14.9 | ) |  | 8.3 |  |  | 11.4 |
State |  | (10.4 | ) |  | — |  |  | — |
Non-U.S. |  | .5 |  |  | .1 |  |  | — |
Total deferred income tax (expense) benefit |  | (24.8 | ) |  | 8.4 |  |  | 11.4 |
Total income tax (expense) benefit |  | $ | (29.3 | ) |  | $ | 4.0 |  |  | $ | 7.8 |
Reconciliation of the U.S. federal statutory income tax rate and actual effective tax rate on pre-tax income | The following table presents a reconciliation of taxes calculated for 2019 and 2018 using the 21% U.S. federal statutory rate and for 2017 using the 35% U.S. federal statutory rate (the tax rate at which the majority of White Mountains’s worldwide operations are taxed) to the income tax (expense) benefit on pre-tax income (loss):
|  | Year Ended December 31,
Millions |  | 2019 |  | 2018 |  | 2017
Tax (expense) benefit at the U.S. statutory rate |  | $ | (85.1 | ) |  | $ | 37.4 |  |  | $ | (2.7 | )
Differences in taxes resulting from: |  |  |  |  |  |  |  |  |
Change in valuation allowance |  | 63.6 |  |  | (31.0 | ) |  | 42.6 |
Non-U.S. earnings, net of foreign taxes |  | 27.1 |  |  | (2.9 | ) |  | 21.5 |
State taxes |  | (17.5 | ) |  | 4.0 |  |  | .6 |
Tax rate changes |  | (5.7 | ) |  | 1.7 |  |  | (44.3 | )
Member’s surplus contributions |  | (3.6 | ) |  | (2.6 | ) |  | (3.0 | )
Withholding tax |  | (1.6 | ) |  | (2.7 | ) |  | (2.0 | )
Tax exempt interest and dividends |  | 1.1 |  |  | .6 |  |  | .5 |
Tax reserve adjustments |  | (.7 | ) |  | (.8 | ) |  | (.3 | )
Officer compensation |  | — |  |  | — |  |  | (4.1 | )
Other, net |  | (6.9 | ) |  | .3 |  |  | (1.0 | )
Total income tax (expense) benefit on pre-tax income (loss) |  | $ | (29.3 | ) |  | $ | 4.0 |  |  | $ | 7.8 |
Schedule of components of deferred income tax assets and liabilities | The following table presents an outline of the significant components of White Mountains’s U.S. federal, state and non-U.S. deferred tax assets and liabilities:
|  | December 31,
Millions |  | 2019 |  | 2018
Deferred tax assets related to: |  |  |  |  |  |
U.S. federal and state net operating and capital loss carryforwards |  | $ | 92.3 |  |  | $ | 95.5 |
Non-U.S. net operating loss carryforwards |  | 41.7 |  |  | 36.6 |
Incentive compensation |  | 15.0 |  |  | 14.1 |
Investment basis difference |  | — |  |  | 11.1 |
Net unrealized investment losses |  | — |  |  | 9.5 |
Accrued interest |  | 5.1 |  |  | — |
Deferred acquisition costs |  | 4.3 |  |  | 3.5 |
Tax credit carryforwards |  | 4.2 |  |  | 4.2 |
Other items |  | 3.4 |  |  | 5.8 |
Total gross deferred tax assets |  | 166.0 |  |  | 180.3 |
Less: valuation allowances |  | 77.9 |  |  | 139.9 |
Total net deferred tax assets |  | 88.1 |  |  | 40.4 |
Deferred tax liabilities related to: |  |  |  |  |  |
Net unrealized investment gains |  | 66.3 |  |  | — |
Member’s surplus contributions |  | 43.2 |  |  | 32.8 |
Investment basis difference |  | 6.6 |  |  | — |
Other items |  | 4.6 |  |  | 5.4 |
Total deferred tax liabilities |  | 120.7 |  |  | 38.2 |
Net deferred tax (liability) asset |  | $ | (32.6 | ) |  | $ | 2.2 |
Schedule of net operating and capital loss carryforwards by expiration dates and the deferred tax assets thereon | The following table presents net operating loss and capital loss carryforwards as of December 31, 2019, the expiration dates and the deferred tax assets thereon:
|  | December 31, 2019
Millions |  | United States |  | Luxembourg |  | United Kingdom |  | Israel |  | Total
2019-2023 |  | $ | .1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | .1 |
2024-2028 |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
2029-2038 |  | 302.6 |  |  | 58.0 |  |  | — |  |  | — |  |  | 360.6 |
No expiration date |  | 117.4 |  |  | 28.5 |  |  | 18.7 |  |  | 73.6 |  |  | 238.2 |
Total |  | $ | 420.1 |  |  | $ | 86.5 |  |  | $ | 18.7 |  |  | $ | 73.6 |  |  | $ | 598.9 |
Gross deferred tax asset |  | $ | 88.0 |  |  | $ | 21.6 |  |  | $ | 3.2 |  |  | $ | 16.9 |  |  | $ | 129.7 |
Valuation allowance |  | (63.5 | ) |  | (21.5 | ) |  | (3.0 | ) |  | (16.9 | ) |  | (104.9 | )
Net deferred tax asset |  | $ | 24.5 |  |  | $ | .1 |  |  | $ | .2 |  |  | $ | — |  |  | $ | 24.8 |
Reconciliation of changes in the amount of unrecognized tax benefits | The following table presents a reconciliation of the beginning and ending amount of unrecognized tax benefits from 2017 to 2019:
Millions |  | Permanent Differences (1) |  | Temporary Differences (2) |  | Interest and Penalties (3) |  | Total
Balance at December 31, 2016 |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Changes in prior year tax positions |  | .1 |  |  | — |  |  | — |  |  | .1 |
Tax positions taken during the current year |  | .2 |  |  | — |  |  | — |  |  | .2 |
Balance at December 31, 2017 |  | .3 |  |  | — |  |  | — |  |  | .3 |
Changes in prior year tax positions |  | .8 |  |  | — |  |  | — |  |  | .8 |
Balance at December 31, 2018 |  | 1.1 |  |  | — |  |  | — |  |  | 1.1 |
Tax positions taken during the current year |  | 1.3 |  |  | — |  |  | — |  |  | 1.3 |
Balance at December 31, 2019 |  | $ | 2.4 |  |  | $ | — |  |  | $ | — |  |  | $ | 2.4 |
(1) | Represents the amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate.
(2) | Represents the amount of unrecognized tax benefits that, if recognized, would create a temporary difference between the reported amount of an item in White Mountains’s Consolidated Balance Sheet and its tax basis.
(3) Net of tax benefit.

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
Name: | us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
Name: | us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
Name: | us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure for tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities and other income tax contingencies. Includes, but is not limited to, interest and penalties, reconciliation of unrecognized tax benefits, unrecognized tax benefits that would affect the effective tax rate, tax years that remain subject to examination by tax jurisdictions, and information about positions for which it is reasonably possible that amounts unrecognized will significantly change within 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32840-109319 + Details
Name: | us-gaap_SummaryOfIncomeTaxContingenciesTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of net operating and capital loss carryforwards and related disclosure such as the expiration dates and the deferred tax assets thereon. + References No definition available. + Details
Name: | wtm_ScheduleOfNetOperatingAndCapitalLossCarryforwardsByExpirationDateAndDeferredTaxAssetTableTextBlock
Namespace Prefix: | wtm_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration