Stockholders' Equity - Assumptions For Stock Options (Details) - Stock Options	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Method and assumptions on valuation of stock options
Expected volatility (as a percent)	34.80%	33.10%
Risk-free interest rate (as a percent)	1.60%	2.00%
Expected term of options	5 years 9 months 18 days	5 years 9 months 18 days
Expected forfeiture rate (as a percent)	5.40%	1.00%
Expected dividend yield (as a percent)	0.00%	0.00%

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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- Definition

The weighted average forfeiture rate assumption used by an entity in valuing an award based upon its own shares. The expected forfeiture rate may be derived from historical employee turnover rates and expectations about the future.

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No definition available.

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