Other	6 Months Ended
Jun. 30, 2011
Notes to Financial Statements [Abstract]
Other	Debt During the six months ended June 30, 2011, we made principal payments of $44.4 million and $5.0 million on our senior secured non-recourse floating rate notes issued by Northwind Holdings, LLC and Tailwind Holdings, LLC, respectively. During the first quarter of 2011, the remaining $225.1 million of our 7.625% senior notes due March 2011 matured. At June 30, 2011, short-term debt consisted of $140.4 million of securities lending transactions. Income Tax At June 30, 2011, we had a liability of $135.3 million for unrecognized tax benefits, $120.1 million of which is associated with deferred tax assets. The total unrecognized tax benefit that would impact the effective tax rate, if recognized, is $15.2 million. The interest expense and penalties related to unrecognized tax expense in our consolidated statements of income was $1.5 million and $2.6 million for the three and six months ended June 30, 2011, respectively, and $1.3 million and $2.5 million for the three and six months ended June 30, 2010, respectively. During 2009, we had a conference with the Internal Revenue Service (IRS) with respect to our appeal of audit adjustments for the years 1999 to 2004. Although we have not yet reached a final settlement with the IRS for these years, it is reasonably possible that this appeal will be resolved in whole or in part within 12 months and that statutes of limitations may expire in multiple jurisdictions within the same period. As a result, it is reasonably possible that our liability for unrecognized tax benefits could decrease within 12 months by $0 million to $40.0 million. We believe sufficient provision has been made for all uncertain tax provisions and that any adjustments by tax authorities with respect to such positions would not have a material adverse effect on our financial position, liquidity, or results of operations. In March 2010, the Patient Protection and Affordable Care Act and the Health Care and Education Reconciliation Act of 2010 were signed into law. Among other things, the new legislation reduces the tax benefits available to an employer that receives a postretirement prescription drug coverage subsidy from the federal government under the Medicare Prescription Drug, Improvement and Modernization Act of 2003. Under the new legislation, to the extent our future postretirement prescription drug coverage expenses are reimbursed under the subsidy program, the expenses covered by the subsidy will no longer be tax deductible after 2012. Employers that receive the subsidy must recognize the deferred tax effects relating to the future postretirement prescription drug coverage in the period the legislation was enacted. Our income tax expense for the three months ended March 31, 2010 includes a non-cash tax charge of $10.2 million to reflect the impact of the tax law change. In July 2011, an income tax rate reduction was enacted which reduced the tax rate in the U.K. from 27 percent to 26 percent retroactive to April 2011 and from 26 percent to 25 percent effective April 2012. We are required to adjust deferred tax assets and liabilities through income on the date of enactment of a rate change. We will record a reduction of approximately $5.0 million to $7.0 million in our income tax expense in the third quarter of 2011 to reflect the impact of the rate change on our net tax liability related to our U.K. operations.

Debt

During the six months ended June 30, 2011, we made principal payments of $44.4 million and $5.0 million on our senior secured non-recourse floating rate notes issued by Northwind Holdings, LLC and Tailwind Holdings, LLC, respectively.

During the first quarter of 2011, the remaining $225.1 million of our 7.625% senior notes due March 2011 matured.

At June 30, 2011, short-term debt consisted of $140.4 million of securities lending transactions.

Income Tax

At June 30, 2011, we had a liability of $135.3 million for unrecognized tax benefits, $120.1 million of which is associated with deferred tax assets. The total unrecognized tax benefit that would impact the effective tax rate, if recognized, is $15.2 million. The interest expense and penalties related to unrecognized tax expense in our consolidated statements of income was $1.5 million and $2.6 million for the three and six months ended June 30, 2011, respectively, and $1.3 million and $2.5 million for the three and six months ended June 30, 2010, respectively.

During 2009, we had a conference with the Internal Revenue Service (IRS) with respect to our appeal of audit adjustments for the years 1999 to 2004. Although we have not yet reached a final settlement with the IRS for these years, it is reasonably possible that this appeal will be resolved in whole or in part within 12 months and that statutes of limitations may expire in multiple jurisdictions within the same period. As a result, it is reasonably possible that our liability for unrecognized tax benefits could decrease within 12 months by $0 million to $40.0 million. We believe sufficient provision has been made for all uncertain tax provisions and that any adjustments by tax authorities with respect to such positions would not have a material adverse effect on our financial position, liquidity, or results of operations.

In March 2010, the Patient Protection and Affordable Care Act and the Health Care and Education Reconciliation Act of 2010 were signed into law. Among other things, the new legislation reduces the tax benefits available to an employer that receives a postretirement prescription drug coverage subsidy from the federal government under the Medicare Prescription Drug, Improvement and Modernization Act of 2003. Under the new legislation, to the extent our future postretirement prescription drug coverage expenses are reimbursed under the subsidy program, the expenses covered by the subsidy will no longer be tax deductible after 2012. Employers that receive the subsidy must recognize the deferred tax effects relating to the future postretirement prescription drug coverage in the period the legislation was enacted. Our income tax expense for the three months ended March 31, 2010 includes a non-cash tax charge of $10.2 million to reflect the impact of the tax law change.

In July 2011, an income tax rate reduction was enacted which reduced the tax rate in the U.K. from 27 percent to 26 percent retroactive to April 2011 and from 26 percent to 25 percent effective April 2012. We are required to adjust deferred tax assets and liabilities through income on the date of enactment of a rate change. We will record a reduction of approximately $5.0 million to $7.0 million in our income tax expense in the third quarter of 2011 to reflect the impact of the rate change on our net tax liability related to our U.K. operations.