Represents the number of equity programs.

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Represents the numerator of the ratio which is used to count awards other than options and Stock Appreciation Rights against the share limit for awards to be issued under a share-based compensation arrangement.

+ References

No definition available.

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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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).

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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No definition available.

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Number of share options (or share units) exercised during the current period.

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Note 10 - Stock-based Compensation (Details Textual)	1 Months Ended		12 Months Ended
Note 10 - Stock-based Compensation (Details Textual)	Nov. 30, 2015 $ / shares shares	Jul. 31, 2007 shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares
Restricted Stock [Member] \| 2006 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			0
Restricted Stock [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options \| $			$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			0
Allocated Share-based Compensation Expense \| $				$ 100,000	$ 700,000
Employee Stock Option [Member] \| 2006 Stock Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
Employee Stock Option [Member] \| 2006 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			4 years
Employee Stock Option [Member] \| HDI 2011 Stock Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			30 days
Employee Stock Option [Member] \| HDI 2011 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			4 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.00%	0.00%	0.00%
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			1 year
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			5 years
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Executive Officer [Member] \| Vest in Equal Installments on Each of the First Three Anniversaries [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Other Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Restricted Stock Units (RSUs) [Member] \| 2006 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			1,154,157
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	57,391		726,784
Restricted Stock Units (RSUs) [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options \| $			$ 13,400,000	$ 13,800,000	$ 11,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			1,154,000	910,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			727,000
Allocated Share-based Compensation Expense \| $			$ 7,900,000	$ 5,700,000	$ 4,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			1 year 58 days
Non-qualified Stock Options [Member] \| 2006 Stock Plan [Member] \| Certain HMS Directors, Executive Officers, and Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	612,391
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price \| $ / shares	$ 11.20
Non-qualified Stock Options [Member] \| 2006 Stock Plan [Member] \| Directors and Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	555,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price \| $ / shares	$ 14
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	125.00%
Restricted Stock Units Expected to Vest [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			1,029,972	813,346	571,204
2006 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			4,952,950
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			18,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			3,413,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options and Stock Appreciation Rights, Ratio Applied for Calculation of Awards Against Limit, Numerator			1.85
Deferred Compensation Arrangement with Individual, Maximum Contractual Term			7 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures			2,442,081
HDI 2011 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			77,128
Share-based Compensation Arrangement By Share-based Payment Award, Number of Equity Programs			2
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			836,122
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			366,806
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
The 1999 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				74,290
Cost of Sales [Member]
Allocated Share-based Compensation Expense \| $			$ 6,200,000	$ 5,100,000	$ 4,500,000
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense \| $			$ 8,100,000
Former CFO [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			180,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures		180,000
Allocated Share-based Compensation Expense \| $			$ 6,400,000	7,600,000	6,700,000
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation \| $			$ 1,569,000	$ 1,795,000	$ 5,233,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number			5,030,000	4,101,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price \| $ / shares			$ 14.69
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares			$ 5.37	$ 7.59	$ 7.07
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			577,559	516,552	1,305,538
Proceeds from Stock Options Exercised \| $			$ 4,187,000	$ 4,110,000	$ 9,260,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value \| $			5,900,000	$ 6,500,000	$ 23,900,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options \| $			$ 14,500,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			1 year 153 days