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Stock-Based Compensation - Stock Options by Exercise Price Range (Details)	3 Months Ended
	Mar. 31, 2016 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	392,019
Options outstanding, weighted average remaining contractual life (in years)	5 years 3 days
Options outstanding, weighted average exercise price (in USD per share)	$ 19.28
Options exercisable, shares | shares	336,187
Options exercisable, weighted average exercise price (in USD per share)	$ 18.22
$0.01-15.70
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	79,852
Options outstanding, weighted average remaining contractual life (in years)	3 years 4 months 32 days
Options outstanding, weighted average exercise price (in USD per share)	$ 10.67
Options exercisable, shares | shares	79,852
Options exercisable, weighted average exercise price (in USD per share)	$ 10.67
Range of exercise prices, lower limit (in USD per share)	0.01
Range of exercise prices, upper limit (in USD per share)	$ 15.70
$15.71-17.81
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	85,750
Options outstanding, weighted average remaining contractual life (in years)	3 years 3 months 87 days
Options outstanding, weighted average exercise price (in USD per share)	$ 17.55
Options exercisable, shares | shares	85,750
Options exercisable, weighted average exercise price (in USD per share)	$ 17.55
Range of exercise prices, lower limit (in USD per share)	15.71
Range of exercise prices, upper limit (in USD per share)	$ 17.81
$17.82-20.48
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	118,917
Options outstanding, weighted average remaining contractual life (in years)	3 years 11 months 30 days
Options outstanding, weighted average exercise price (in USD per share)	$ 19.59
Options exercisable, shares | shares	118,917
Options exercisable, weighted average exercise price (in USD per share)	$ 19.59
Range of exercise prices, lower limit (in USD per share)	17.82
Range of exercise prices, upper limit (in USD per share)	$ 20.48
$20.49-33.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	107,500
Options outstanding, weighted average remaining contractual life (in years)	8 years 5 months 32 days
Options outstanding, weighted average exercise price (in USD per share)	$ 26.72
Options exercisable, shares | shares	51,668
Options exercisable, weighted average exercise price (in USD per share)	$ 27.85
Range of exercise prices, lower limit (in USD per share)	20.49
Range of exercise prices, upper limit (in USD per share)	$ 33.36

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+ References

No definition available.

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- Definition

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

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- Definition

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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- Definition

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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- Definition

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

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- Definition

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
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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