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CashReceivedFromProceedsByParticipants

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- Definition

ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedAggregatePurchaseValue

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- Definition

ValueOfOneYearStockOptionPercentage

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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.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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

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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

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Number of suspense shares held by the Employee Stock Option Plan at balance sheet date. Suspense shares are shares that have not been released, committed to be released or allocated to individual participant accounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

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Stock Based Compensation Employee Stock Purchase Plan Details (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Aug. 31, 2015	Jul. 31, 2015	Dec. 31, 2014	Aug. 31, 2014	Jul. 31, 2014	Dec. 31, 2013	Aug. 31, 2013	Jul. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	0
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
AllottedValueMaximum	$ 25,000
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,194,928
ThresholdPeriodWorkedPerWeekByEmployees	20
ShareBasedCompensationArrangementByShareBasedPaymentAwardSubscriptionPeriodBeginning	August 1
ShareBasedCompensationArrangementByShareBasedPaymentAwardSubscriptionPeriodEnding	July 31
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	85.00%
ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfMarketPrice	15.00%
ValueOfOneYearStockOptionPercentage	85.00%
EstimatedFairValuePerShareOption		$ 6.43			$ 6.39			$ 8.36
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period			539,389			512,521			487,672
ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedAggregatePurchaseValue			$ 14,400,000			$ 13,400,000			$ 10,500,000
ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedAggregatePurchasePricePerShare			$ 26.62			$ 26.16			$ 21.44
Shares held in Employee Stock Option Plan, Suspense Shares	231,803			235,794			222,526
CashReceivedFromProceedsByParticipants	$ 6,800,000			$ 6,300,000			$ 5,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	17,000,000