Employee Share-Based Incentive Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2016

White Mountains

Share-based compensation arrangement by share-based payment award

Summary of performance share activity

The following summarizes performance share activity for the years ended December 31, 2016, 2015 and 2014 for performance shares granted under the WTM Incentive Plan:

	Year Ended December 31,
	2016					2015					2014
$ in millions	Target Performance Shares Outstanding		Accrued Expense			Target Performance Shares Outstanding		Accrued Expense			Target Performance Shares Outstanding		Accrued Expense
Beginning of period	93,654		$	57.7		111,257		$	44.4		108,605		$	54.9
Shares paid or expired(1)	(36,294	)	(41.0		)	(42,959	)	(30.8		)	(33,730	)	(24.5		)
New grants	22,615		—			29,195		—			39,590		—
Assumed forfeitures and cancellations(2)	378		.5			(3,839	)	(.3		)	(3,208	)	(.1		)
Expense recognized	—		25.2			—		44.4			—		14.1
End of period (3)	80,353		$	42.4		93,654		$	57.7		111,257		$	44.4

⁽¹⁾  WTM performance share payments in 2016 for the 2013-2015 performance cycle ranged from 140% to 142% of target. WTM performance shares payments in 2015 for the 2012-2014 performance cycle ranged from 91% to 145.5% of target. WTM performance shares payments in 2014 for the 2011-2013 performance cycle ranged from 88% to 131.5% of target.

⁽²⁾  Amounts include changes in assumed forfeitures, as required under GAAP.

⁽³⁾  Outstanding performance share awards as of December 31, 2016, 2015 and 2014 exclude 7,315, 10,826 and 12,607 unvested performance shares awards for employees of Sirius Group.

Summary of performance shares outstanding and accrued expense for performance shares awarded under an Incentive Plan

The following table summarizes performance shares outstanding and accrued expense for performance shares awarded under the WTM Incentive Plan as of December 31, 2016 for each performance cycle:

$ in millions	Target WTM Performance Shares Outstanding		Accrued Expense
Performance cycle:
2016 – 2018	19,615		$	5.4
2015 – 2017	31,795		19.1
2014 – 2016	30,167		18.6
Sub-total	81,577		43.1
Assumed forfeitures	(1,224	)	(.7		)
Total at December 31, 2016	80,353		$	42.4

Schedule of Nonvested Restricted Stock Activity [Table Text Block]

The following outlines the unrecognized compensation cost associated with the outstanding restricted share awards under the WTM Incentive Plan for the years ended December 31, 2016, 2015 and 2014:

	Year Ended December 31,
	2016					2015					2014
$ in millions	Restricted Shares		Unamortized Issue Date Fair Value			Restricted Shares		Unamortized Issue Date Fair Value			Restricted Shares		Unamortized Issue Date Fair Value
Non-vested,
Beginning of period	70,675		$	15.7		83,314		$	14.3		94,130		$	17.0
Issued	25,365		20.2			23,640		15.7			23,440		13.1
Vested	(24,620	)	—			(36,279	)	—			(33,205	)	—
Forfeited	(800	)	(.3		)	—		—			(1,051	)	(.5		)
Expense recognized	—		(15.9		)	—		(14.3		)	—		(15.3		)
End of period (1)	70,620		$	19.7		70,675		$	15.7		83,314		$	14.3

⁽¹⁾  Outstanding restricted share awards as of December 31, 2016, 2015 and 2014 include 5,235, 9,205, and 12,477 unvested restricted shares for employees of Sirius Group.

OneBeacon

Share-based compensation arrangement by share-based payment award

Summary of performance share activity

The following summarizes activity for the years ended December 31, 2016, 2015 and 2014 for OneBeacon performance shares granted under the OneBeacon Incentive Plan:

	Year Ended December 31,
	2016					2015					2014
$ in millions	Target Performance Shares Outstanding		Accrued Expense			Target Performance Shares Outstanding		Accrued Expense			Target Performance Shares Outstanding		Accrued Expense
Beginning of period	449,435		$	1.4		517,470		$	3.4		493,421		$	4.0
Payments and deferrals(1)	(167,300	)	(.6		)	(181,290	)	(1.5		)	(142,138	)	(1.0		)
New awards	163,150		—			154,887		—			165,800		—
Forfeitures and cancellations(2)	7,234		—			(41,632	)	(.1		)	387		—
Expense recognized	—		.8			—		(.4		)	—		.4
End of period	452,519		$	1.6		449,435		$	1.4		517,470		$	3.4

⁽¹⁾  OneBeacon performance share payments in 2016 for the 2013-2015 performance cycle were at 24.3% of target. OneBeacon performance share payments in 2015 for the 2012-2014 performance cycle were at 45.7% of target. OneBeacon performance share payments in 2014 for the 2011-2013 performance cycle were at 37.1% of target.

⁽²⁾  Amounts include changes in assumed forfeitures, as required under GAAP.

Summary of performance shares outstanding and accrued expense for performance shares awarded under an Incentive Plan

The following summarizes OneBeacon performance shares outstanding awarded under the OneBeacon Incentive Plan as of December 31, 2016 for each performance cycle:

$ in millions	Target OneBeacon Performance Shares Outstanding	Accrued Expense
Performance cycle:
2016 – 2018	163,150	$	.9
2015 – 2017	146,659	.7
2014 – 2016	142,710	—
Total at December 31, 2016	452,519	$	1.6

Schedule of Nonvested Restricted Stock Activity [Table Text Block]

The following table summarizes the unrecognized compensation cost associated with the outstanding OneBeacon restricted stock awards for the years ended December 31, 2016, 2015 and 2014.

	Year Ended December 31,
	2016					2015					2014
$ in millions	Restricted Shares		Unamortized Issue Date Fair Value			Restricted Shares		Unamortized Issue Date Fair Value			Restricted Shares		Unamortized Issue Date Fair Value
Beginning of period	382,722		$	2.5		612,500		$	3.5		915,000		$	6.5
Issued	170,650		2.3			75,950		1.1			—		—
Vested	(157,500	)	—			(296,000	)	—			(300,000	)	—
Forfeited	—		—			(9,728	)	(.1		)	(2,500	)	—
Expense recognized	—		(2.7		)	—		(2.0		)	—		(3.0		)
End of period	395,872		$	2.1		382,722		$	2.5		612,500		$	3.5