Stock Plans (Narrative) (Details) (USD $)	2 Months Ended	12 Months Ended
	Feb. 17, 2014	Dec. 31, 2014 ShareBasedCompensationPlan	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at end of period (in dollars per share)		$ 13.23	$ 13.23	10.99	$ 9.94
Exercisable at end of period (in shares)		83,000	83,000	540,000
Number of stock-based compensation plan under which grants were made		6
Number of stock-based compensation plan under which grants were not made		4
Shares authorized for grant under the plans (in shares)		22,540,761
Shares available for grant under the plan (in shares)		14,253,934
Performance Shares
Number of shares granted (in shares)	1,028,000
Aggregate Intrinsic Value [Abstract]
Remaining unrecognized stock compensation		$ 0
Deferred Fee Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant under the plans (in shares)		540,761
EIP Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant under the plans (in shares)		20,000,000
Shares available for grant under the plan (in shares)		13,442,932
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grant under the plans (in shares)			1,124,000
Expense recognized during the period		4,000,000	1,000,000
Performance Shares
Initial period over which target number of performance shares are awarded		90 days
Measurement period		3 years
Number of shares granted (in shares)				979,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized during the period		16,000,000	14,000,000	16,000,000
Restricted Stock
Remaining unrecognized compensation cost associated with unvested restricted stock awards		24,000,000
Weighted average period over which unvested restricted stock awards unrecognized compensation cost is expected to be recognized (in years)		1 year 4 months 24 days
Non-Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at end of period (in dollars per share)		$ 12.10
Exercisable at end of period (in shares)		105,000
Shares authorized for grant under the plans (in shares)		2,540,761
Shares available for grant under the plan (in shares)		811,002
Expense recognized during the period		4,000,000	2,000,000	1,000,000
Non Employee Directors Compensation Plans
Plan units earned during the period (in shares)		237,607	374,383	306,634
Number of directors participating in the plan during the period		12
Cash compensation		1,000,000	1,000,000	1,000,000
Non-Employee Director [Member] | Chair of Retirement Plan Committee [Member]
Non Employee Directors Compensation Plans
Annual stipend		10,000		7,500
Non-Employee Director [Member] | Chair of Nominating and Corporate Governance Committee [Member]
Non Employee Directors Compensation Plans
Annual stipend		15,000		10,000
Non-Employee Director [Member] | Chair of Compensation Committee [Member]
Non Employee Directors Compensation Plans
Annual stipend		20,000
Non-Employee Director [Member] | Chair of Audit Committee [Member]
Non Employee Directors Compensation Plans
Annual stipend		25,000		20,000
Non-Employee Director [Member] | Lead Director [Member]
Non Employee Directors Compensation Plans
Annual stipend		25,000		20,000
Non-Employee Director [Member] | Non-Employee Director [Member]
Non Employee Directors Compensation Plans
Annual retainer for non employee directors in cash		90,000		75,000
Annual retainer for non employee directors cash value of stock units		$ 90,000		75,000