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Stock-Based Compensation - Stock Options Outstanding (Details)	6 Months Ended
	Jun. 30, 2017 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	357,356
Options outstanding, weighted average remaining contractual life (years)	4 years 4 months 36 days
Options outstanding, weighted average exercise price (in USD per share) | $ / shares	$ 20.19
Options exercisable, shares | shares	305,441
Options exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 19.11
$0.01-15.70
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	65,852
Options outstanding, weighted average remaining contractual life (years)	2 years 22 days
Options outstanding, weighted average exercise price (in USD per share) | $ / shares	$ 9.82
Options exercisable, shares | shares	65,852
Options exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 9.82
$15.71-17.81
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	72,750
Options outstanding, weighted average remaining contractual life (years)	2 years 2 months 44 days
Options outstanding, weighted average exercise price (in USD per share) | $ / shares	$ 17.53
Options exercisable, shares | shares	72,750
Options exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 17.53
$17.82-20.48
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	86,836
Options outstanding, weighted average remaining contractual life (years)	2 years 9 months 34 days
Options outstanding, weighted average exercise price (in USD per share) | $ / shares	$ 19.60
Options exercisable, shares | shares	86,836
Options exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 19.60
$20.49-33.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares | shares	131,918
Options outstanding, weighted average remaining contractual life (years)	7 years 8 months 65 days
Options outstanding, weighted average exercise price (in USD per share) | $ / shares	$ 27.23
Options exercisable, shares | shares	80,003
Options exercisable, weighted average exercise price (in USD per share) | $ / shares	$ 27.67

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+ References

No definition available.

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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=96867065&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=96867065&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=96867065&loc=d3e5070-113901

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- Definition

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=96867065&loc=d3e5070-113901

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- Definition

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=96867065&loc=d3e5070-113901

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