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Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases [Abstract]

Schedule of net lease expense

The following table summarizes net lease expense recognized in White Mountains’s consolidated statement of operations for the years ended December 31, 2020 and 2019:

Millions Lease Cost						December 31, 2020						December 31, 2019
Lease cost						$	7.7					$	7.2
Less: sublease income						.4						.4
Net lease cost						$	7.3					$	6.8

Schedule of contractual maturities of lease liabilities

The following table presents the contractual maturities of the lease liabilities associated with White Mountains’s operating lease agreements as of December 31, 2020:

Millions						December 31, 2020
2021						$	7.7
2022						7.3
2023						7.1
2024						5.8
2025						5.1
Thereafter						12.2
Total undiscounted lease payments						45.2
Less: present value adjustment						(6.9)
Operating lease liability						$	38.3

Schedule of lease related assets and liabilities

The following table presents lease related assets and liabilities by reportable segment as of December 31, 2020 and 2019:

						As of December 31, 2020
$ in Millions						HG/BAM						NSM						Kudu						Other Operations						Total						Weighted Average Incremental Borrowing Rate (1)
ROU lease asset						$	10.1					$	17.1					$	2.0					$	8.4					$	37.6					4.6%
Lease liability						$	10.1					$	17.1					$	2.0					$	9.1					$	38.3

(1) The present value of the remaining lease payments was determined by discounting the lease payments using the incremental borrowing rate.

						December 31, 2019
$ in Millions						HG/BAM						NSM						Kudu						Other Operations						Total						Weighted Average Incremental Borrowing Rate (1)
ROU lease asset						$	10.4					$	4.8					$	2.3					$	5.1					$	22.6					4.6%
Lease liability						$	10.4					$	4.8					$	2.3					$	5.3					$	22.8

(1) The present value of the remaining lease payments was determined by discounting the lease payments using the incremental borrowing rate.

X

- Definition

Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980

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X

- References

No definition available.

+ Details

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X

- Definition

Tabular disclosure of undiscounted cash flows of lessee's operating lease liability. Includes, but is not limited to, reconciliation of undiscounted cash flows to operating lease liability recognized in statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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- Definition

Schedule of Right-of-Use Assets and Lease Liabilities [Table Text Block]

+ References

No definition available.

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