Employee Stock and Incentive Plans - Non-Qualified Stock Options, Range of Exercise Price (Details) - Non-Qualified Stock Options [Member] $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($) $ / shares shares
$39.10 [Member]
Range of Exercise Price [Line Items]
Lower Range Limit	$ 39.10
Upper Range Limit	$ 39.10
Options Outstanding and Exercisable [Abstract]
Number Outstanding \| shares	16,620
Outstanding - Weighted Average Remaining Contractual Life (Years/Months)	2 years 1 month
Outstanding - Weighted Average Exercise Price	$ 39.10
Outstanding - Aggregate Intrinsic Value (Millions) \| $	$ 0.2
Number Exercisable \| shares	16,620
Exercisable - Weighted Average Remaining Contractual Life (Years/Months)	2 years 1 month
Exercisable - Weighted Average Exercise Price	$ 39.10
Exercisable - Aggregate Intrinsic Value (Millions) \| $	$ 0.2
$44.15 [Member]
Range of Exercise Price [Line Items]
Lower Range Limit	$ 44.15
Upper Range Limit	$ 44.15
Options Outstanding and Exercisable [Abstract]
Number Outstanding \| shares	2,306
Outstanding - Weighted Average Remaining Contractual Life (Years/Months)	1 month
Outstanding - Weighted Average Exercise Price	$ 44.15
Outstanding - Aggregate Intrinsic Value (Millions) \| $	$ 0.0
Number Exercisable \| shares	2,306
Exercisable - Weighted Average Remaining Contractual Life (Years/Months)	1 month
Exercisable - Weighted Average Exercise Price	$ 44.15
Exercisable - Aggregate Intrinsic Value (Millions) \| $	$ 0.0
$48.65 [Member]
Range of Exercise Price [Line Items]
Lower Range Limit	$ 48.65
Upper Range Limit	$ 48.65
Options Outstanding and Exercisable [Abstract]
Number Outstanding \| shares	20,728
Outstanding - Weighted Average Remaining Contractual Life (Years/Months)	1 year 1 month
Outstanding - Weighted Average Exercise Price	$ 48.65
Outstanding - Aggregate Intrinsic Value (Millions) \| $	$ 0.1
Number Exercisable \| shares	20,728
Exercisable - Weighted Average Remaining Contractual Life (Years/Months)	1 year 1 month
Exercisable - Weighted Average Exercise Price	$ 48.65
Exercisable - Aggregate Intrinsic Value (Millions) \| $	$ 0.1

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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

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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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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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Weighted average remaining contractual term of outstanding stock options, 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
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