Represents the number of types of awards outstanding under the entity's stock incentive plans.

No definition available.

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Represents the number of stock incentive plans sponsored by the entity.

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Of the four sponsored plans, the number of plans under which no new grants are being made.

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Number of Legacy Orbital Sciences stock-based incentive plans

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Number of legacy ATK stock-based incentive plans

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions Expected Volatility Rate Period

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No definition available.

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The maximum term of equity-based award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

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No definition available.

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The minimum term of equity-based award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

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No definition available.

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Share reserved for vesting of restricted stock units for fiscal 2014-2016

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No definition available.

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Shares payable upon achievement of absolute sales growth

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Shares payable upon achievement of earnings per share growth

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Shares reserved for vesting of restricted stock units fiscal 2015-2017

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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No definition available.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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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No definition available.

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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 estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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No definition available.

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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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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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stockholders' Equity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($) award plan $ / shares shares	Mar. 31, 2015 USD ($) $ / shares shares	Mar. 31, 2014 USD ($) $ / shares shares	Mar. 31, 2013 shares
Stock-Based Compensation
Number of authorized shares of preferred stock	5,000,000
Par value of preferred stock (in dollars per share) \| $ / shares	$ 1.00
Number of stock-based incentive plans \| plan	6
Number of plans under which no new grants are being made \| plan	5
Number of types of awards outstanding under the entity's stock incentive plans \| award	5
Share reserved for vesting of restricted stock units for fiscal 2014-2016	40,707
Shares reserved for vesting of restricted stock units fiscal 2015-2017	55,677
Number of shares reserved			0	0
Restricted stock granted to non-employee directors and certain key employees (in shares)		0	0
Weighted average fair value of awards granted (in dollars per share) \| $ / shares	$ 74.88	$ 81.88	$ 114.65
Weighted average assumptions used in estimating the value of the award
Expected award life			7 years
Share-based compensation, additional disclosures
Total pre-tax stock-based compensation expense \| $	$ 19,521	$ 25,325	$ 12,701
Total income tax benefit recognized in the income statement for share-based compensation \| $	$ 7,544	$ 8,761	$ 4,874
Performance Shares
Stock-Based Compensation
Number of shares reserved	157,799
Shares payable upon achievement of earnings per share growth	50.00%
Shares payable upon achievement of absolute sales growth	50.00%
TSR Awards
Stock-Based Compensation
Weighted average fair value of awards granted (in dollars per share) \| $ / shares	$ 94.93
Weighted average assumptions used in estimating the value of the award
Risk-free rate	1.02%	1.02%
Expected volatility	22.81%	22.81%
Expected dividend yield	1.78%	1.78%
Expected award life	3 years	3 years
Restricted Stock
Stock-Based Compensation
Restricted stock granted to non-employee directors and certain key employees (in shares)	86,108	139,093	127,425
Restricted Stock \| Minimum
Share-based compensation, additional disclosures
Award vesting period (in years)	1 year
Restricted Stock \| Maximum
Share-based compensation, additional disclosures
Award vesting period (in years)	3 years
Stock options
Weighted average assumptions used in estimating the value of the award
Risk-free rate	1.99%	1.82%
Expected volatility	27.91%	27.67%
Expected dividend yield	1.17%	0.99%
Expected award life	7 years	7 years
Share-based compensation, additional disclosures
Minimum terms of options (in years)	7 years
Maximum terms of options (in years)	10 years
Number of years upon which expected volatility is based	7 years
Weighted average fair value of options granted (in dollars per share) \| $ / shares	$ 20.80	$ 39.81	$ 35.34
Stock options \| Minimum
Weighted average assumptions used in estimating the value of the award
Risk-free rate			1.86%
Expected volatility			25.95%
Expected dividend yield			1.27%
Share-based compensation, additional disclosures
Award vesting period (in years)	1 year
Stock options \| Maximum
Weighted average assumptions used in estimating the value of the award
Risk-free rate			2.07%
Expected volatility			26.71%
Expected dividend yield			1.58%
Share-based compensation, additional disclosures
Award vesting period (in years)	3 years
Legacy ATK Plans
Stock-Based Compensation
Legacy ATK stock-based incentive plans \| plan	3
Legacy Orbital Plans
Stock-Based Compensation
Legacy Orbital Sciences stock-based incentive plans \| plan	2
2005 Stock Incentive Plan
Stock-Based Compensation
Number of authorized common shares	3,750,000
Number of available shares to be granted	3,704,016