Commitments and Contingencies (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commitments and Contingencies Other Details [Line Items]
Provision for uncollectible premiums receivable	$ 8,000,000	$ 8,000,000
Rent expense	33,600,000us-gaap_OperatingLeasesRentExpenseNet	33,000,000us-gaap_OperatingLeasesRentExpenseNet	36,300,000us-gaap_OperatingLeasesRentExpenseNet
Restructuring costs incurred	11,000,000	58,000,000
IT and computer agreements and lease contracts	14,000,000
Lease arrangements [abstract]
2015	27,393,000
2016	26,092,000
2017	25,509,000
2018	12,358,000
2019	5,068,000
2020 through 2022	685,000
Total future minimum rental payments	97,105,000
Total future sub-lease rental income through 2019	5,253,000
Structured Letter Of Credit [Member]
Commitments and Contingencies Other Details [Line Items]
LOC obligations guaranteed as of balance sheet date	61,000,000	100,000,000
Line Of Credit Facility Term	10 years
Maturity date of facility	Dec. 29, 2020
Strategic Investments [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2015	49,000,000
2016	39,000,000
2017	34,000,000
2018	7,000,000
2019	3,000,000
Total	$ 132,000,000

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The term of the line of credit facility, from issuance date to first maturity date.

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The floor amount as of the balance sheet date that the entity must expend to satisfy the terms of disclosed arrangements (excluding long-term commitments) in which the entity has agreed to expend funds to procure goods or services from one or more suppliers, other than under a long-term purchase commitment or an unconditional purchase obligation.

+ References

No definition available.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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-Publisher FASB

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Date the credit facility terminates, in CCYY-MM-DD format.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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