v2.4.0.6
Long-Term Compensation (Details 2) (USD $)
12 Months Ended
Dec. 31, 2009
Dec. 31, 2011
Restricted Stock Units, Contingent Performance Shares and Performance Shares Awards [Member]
Non-vested RSUs, CPSs and PSAs    
Number of Options, Beginning balance   0
Weighted Average Grant-Date Fair Value, Beginning balance   $ 0.00
AMB awards   1,228,944
Weighted Average Grant-Date Fair Value, AMB awards   $ 34.07
Granted 370,320 15,500
Weighted Average Grant-Date Fair Value, Granted   $ 33.82
Number of Options, Distributed   (44,060)
Weighted Average Grant-Date Fair Value, Distributed   $ 34.07
Number of Options, Forfeited   (7,402)
Weighted Average Grant-Date Fair Value, Forfeited   $ 34.07
Number of Options, Ending balance   1,192,982
Weighted Average Grant-Date Fair Value, Ending balance   $ 34.07