Management Stock Plans - Bonus Stock Plans (Details) - Stock Bonus Plans - Restricted Stock Units - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Management Stock Plans
Units Granted (in shares)	17,867,547	12,599,070
Vesting Duration	3 years
April 15
Management Stock Plans
Units Granted (in shares)	9,135,710
Fair Value of Stock (in usd per share)	$ 5.40
Vesting Duration	3 years
June 1
Management Stock Plans
Units Granted (in shares)	194,525
Fair Value of Stock (in usd per share)	$ 5.63
Vesting Duration	3 years
July 10
Management Stock Plans
Units Granted (in shares)	56,056
Fair Value of Stock (in usd per share)	$ 5.91
Vesting Duration	3 years
September 15
Management Stock Plans
Units Granted (in shares)	46,552
Fair Value of Stock (in usd per share)	$ 5.80
Vesting Duration	3 years
July 15
Management Stock Plans
Units Granted (in shares)	11,555,962
Fair Value of Stock (in usd per share)	$ 7.18
Vesting Duration	3 years
May 18
Management Stock Plans
Units Granted (in shares)	550,140
Fair Value of Stock (in usd per share)	$ 7.18
Vesting Duration	46 months
August 7
Management Stock Plans
Units Granted (in shares)	6,964
Fair Value of Stock (in usd per share)	$ 7.18
Vesting Duration	3 years
January 15
Management Stock Plans
Units Granted (in shares)	486,004
Fair Value of Stock (in usd per share)	$ 6.43
Vesting Duration	25 months
March 15 Three Year Duration
Management Stock Plans
Units Granted (in shares)	44,500
Fair Value of Stock (in usd per share)	$ 4.96
Vesting Duration	3 years
March 15 Two Year Duration
Management Stock Plans
Units Granted (in shares)	167,339
Fair Value of Stock (in usd per share)	$ 4.96
Vesting Duration	24 months
June 15
Management Stock Plans
Units Granted (in shares)	16,393,770
Fair Value of Stock (in usd per share)	$ 4.59
Vesting Duration	3 years
July 11
Management Stock Plans
Units Granted (in shares)	552,941
Fair Value of Stock (in usd per share)	$ 4.44
Vesting Duration	3 years
February 15
Management Stock Plans
Units Granted (in shares)	53,375
Fair Value of Stock (in usd per share)	$ 4.89
Vesting Duration	28 months
Dividend equivalent units credited in 2016
Management Stock Plans
Units Granted (in shares)	655,622
Fair Value of Stock (in usd per share)	$ 0.00