Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Operating Loss Carryforwards [Line Items]
Tax Adjustments, Settlements, and Unusual Provisions	$ 2.1
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 2.9
Effective income tax rate continuing operations	37.00%	31.30%
Federal statutory tax rate	35.00%	35.00%
Unrecognized Tax Benefits, Probability Threshold of Realizing for Tax Benefits Recognition, Minimum Percentage	50.00%
Unrecognized Tax Benefits, Including Foreign Tax Credits and Penalties and Interest	$ 5.8

Unrecognized Tax Benefits, Including Foreign Tax Credits and Penalties and Interest

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- Definition

Unrecognized Tax Benefits, Probability Threshold of Realizing for Tax Benefits Recognition, Minimum Percentage

+ References

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ 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 (h)(1)(i)
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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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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 740
-SubTopic 10
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