Cash And Cash Equivalents Plan Assets

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- Definition

Defined Benefit Plan, Accelerated Recognition Of Gains (Losses)

+ References

No definition available.

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- Definition

Defined benefit plan, additional cost contribution

+ References

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- Definition

Defined Benefit Plan Contributions By Plan Participants On Plan Assets

+ References

No definition available.

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- Definition

Defined Benefit Plan Fair Value Of Investments

+ References

No definition available.

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- Definition

Defined Benefit Plan Foreign Currency Exchange Rate

+ References

No definition available.

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- Definition

Defined benefit plan, interest rate used calculating annual transition pension adjustment for specified completed period of service

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No definition available.

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- Definition

Defined benefit plan, interest rate used calculating annual transition pension adjustment, thereafter

+ References

No definition available.

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- Definition

Defined benefit plan, maximum number of years of completed service used in calculating the annual transition pension adjustment

+ References

No definition available.

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- Definition

Defined Benefit Plan, Maximum Percentage Contributed By Employer

+ References

No definition available.

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- Definition

Percentage of unrecognized net actuarial gains (losses) as projected benefit obligation, amortized as component of net periodic pension cost

+ References

No definition available.

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- Definition

Retirement Plans [Line Items]

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No definition available.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
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- Definition

If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Curtailment
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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

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- Definition

The amount that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

+ References

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-Subparagraph (b)(8)
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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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-Publisher FASB
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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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Pension Plan (Narrative) (Details)		12 Months Ended
Pension Plan (Narrative) (Details)	Jan. 01, 2005	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Retirement Plans [Line Items]
Interest rate used calculating annual transition pension adjustment for specified completed period of service	5.00%
Defined benefit plan, maximum number of years of completed service used in calculating the annual transition pension adjustment	35 years
Interest rate used calculating annual transition pension adjustment, thereafter	3.00%
Projected benefit obligation, defined benefit pension plans exceeds plan assets		$ 28,000,000
Employee contributions		300,000	$ 400,000
Curtailment gain		1,800,000
Lump-sum settlements			55,100,000
Settlement loss			(12,100,000)	$ (400,000)
Accelerated recognition of gains (losses)			$ 1,300,000
Estimated future contributions in next fiscal year		$ 0
Maximum percentage contributed by employer		6.00%	6.00%	6.00%
Defined contribution plan expense		$ 20,100,000	$ 19,900,000	$ 18,300,000
Additional cost contribution		2,000,000	2,100,000	2,800,000
Additional cost contribution		$ 4,800,000	$ 6,100,000	$ 5,000,000
Defined Benefit Plan Foreign Currency Exchange Rate		1.47
Minimum [Member]
Retirement Plans [Line Items]
Percentage of unrecognized net actuarial gains (losses) as projected benefit obligation, amortized as component of net periodic pension cost		10.00%
Chaucer Pension Plan [Member]
Retirement Plans [Line Items]
Projected benefit obligation, defined benefit pension plans exceeds plan assets		$ 5,000,000
Expected rate of return on plan assets		5.45%	6.55%	6.70%
Defined benefit plan, target allocation percentage		100.00%	100.00%
Fair value of total plan asset		$ 123,500,000	$ 131,800,000	$ 120,200,000
Invested assets, fair value		122,900,000	130,300,000
Cash and cash equivalents, fair value		600,000	$ 1,500,000
Estimated future contributions in next fiscal year		$ 700,000
Chaucer Pension Plan [Member] \| Equity Securities
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		56.00%	57.00%
Fair value of total plan asset		$ 69,400,000	$ 75,400,000
Chaucer Pension Plan [Member] \| Fixed Maturities
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		32.00%	32.00%
Fair value of total plan asset		$ 38,700,000	$ 40,900,000
Chaucer Pension Plan [Member] \| Real Estate Funds
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		12.00%	11.00%
Fair value of total plan asset		$ 14,800,000	$ 14,000,000
U.S. Qualified Defined Benefit Plans [Member]
Retirement Plans [Line Items]
Expected rate of return on plan assets		5.00%
Defined benefit plan, target allocation percentage		100.00%	100.00%
Fair value of total plan asset		$ 472,800,000	$ 513,400,000	$ 542,000,000
Settlement loss			$ 10,800,000
Estimated future contributions in next fiscal year		$ 3,200,000
U.S. Qualified Defined Benefit Plans [Member] \| Fixed Income Securities
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		85.00%	85.00%
Fair value of total plan asset		$ 402,300,000	$ 436,400,000
U.S. Qualified Defined Benefit Plans [Member] \| Equity Securities
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		15.00%	15.00%
Fair value of total plan asset		$ 70,500,000	$ 77,000,000
U.S. Qualified Defined Benefit Plans [Member] \| Fixed Maturities
Retirement Plans [Line Items]
Defined benefit plan, target allocation percentage		84.00%	84.00%
Fair value of total plan asset		$ 397,600,000	$ 432,500,000