Closing price of stock on date of stock grant.

No definition available.

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- Definition

Maximum term of the awards granted under the plan.

+ References

No definition available.

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- Definition

Restricted stock awarded subject to performance condition.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award award vesting date.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Percentage of vesting of share-based compensation awards.

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

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Stock Options, Restricted Stock and Restricted Stock Units (Details Textual) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2015	Dec. 31, 2015	May. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized for grants		500,000
Maximum term of the awards granted under the Plan		10 years
Stock-based compensation cost which has not yet been recognized		$ 25.7
Stock-based compensation cost recognized period, in months		33 months
Restricted stock awarded subject to performance condition		467,000
Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grants	71,991		40,867
Vesting percentage	100.00%
Vesting date	Feb. 28, 2019
Closing price of stock on date of stock grant	$ 70.15		$ 48.94
Board of Directors [Member] \| Vesting over three years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for grants			13,797