Stock-based Compensation Plans - Stock Options (Details) - Options	12 Months Ended
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period	7 years
Expiration period after termination, death or retirement	3 years
Award vesting period	4 years
2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period	10 years
Expiration period after termination, death or retirement	3 years
Award vesting period	4 years

Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period After Termination, Death or Retirement

No definition available.

+ Details

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- Definition

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.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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