Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Paragraph 2
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Management Stock Plans - Bonus Stock Plans (Details) - Stock Bonus Plan - Restricted Stock Units - $ / shares								12 Months Ended
	Dec. 16, 2015	Jul. 15, 2015	Sep. 15, 2014	Jul. 10, 2014	Apr. 15, 2014	Jul. 15, 2013	Apr. 15, 2013	Dec. 31, 2015	Dec. 31, 2014
Management Stock Plans
Units Granted								12,505,487	9,238,318
Vesting Duration								3 years
April 15
Management Stock Plans
Units Granted							3,656,340
Fair Value of Stock							$ 6.66
Vesting Duration							3 years
July 15
Management Stock Plans
Units Granted						78,725
Fair Value of Stock						$ 6.67
Vesting Duration						3 years
April 15
Management Stock Plans
Units Granted					9,135,710
Fair Value of Stock					$ 5.40
Vesting Duration					3 years
July 10
Management Stock Plans
Units Granted				56,056
Fair Value of Stock				$ 5.91
Vesting Duration				3 years
September 15
Management Stock Plans
Units Granted			46,552
Fair Value of Stock			$ 5.80
Vesting Duration			3 years
July 15
Management Stock Plans
Units Granted		11,469,343
Fair Value of Stock		$ 7.18
Vesting Duration		3 years
May 18
Management Stock Plans
Units Granted		550,140
Fair Value of Stock		$ 7.18
Vesting Duration		46 months
January 15
Management Stock Plans
Units Granted	486,004
Fair Value of Stock	$ 6.43
Vesting Duration	25 months