Debt (Tables)

12 Months Ended

Dec. 31, 2012

Senior Notes 6.375% Due 2022

Debt Instrument

Senior notes, expressed as percentage of principal amount redeemed, plus accured and unpaid interest, by maturity

2017	103.188	%
2018	102.125	%
2019	101.063	%
2020 and thereafter	100.000	%

Senior Notes 6.75 Percent Due 2020

Debt Instrument

Senior notes, expressed as percentage of principal amount redeemed, plus accured and unpaid interest, by maturity

2015	103.375	%
2016	102.250	%
2017	101.125	%
2018 and thereafter	100.000	%