Mantech International (MANT) 10-K 19 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 17, 2016	Jun. 30, 2015
Entity Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	MANT
Entity Registrant Name	MANTECH INTERNATIONAL CORP
Entity Central Index Key	892,537
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 703,653,216
Class A Common Stock [Member]
Entity Information [Line Items]
Common Stock, Shares Outstanding		24,494,472
Class B Common Stock [Member]
Entity Information [Line Items]
Common Stock, Shares Outstanding		13,191,845

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 41,314,000	$ 23,781,000
Receivables—net	304,253,000	377,156,000
Prepaid expenses and other	23,605,000	18,207,000
Total Current Assets	369,172,000	419,144,000
Goodwill	919,591,000	851,640,000
Other intangible assets—net	154,176,000	155,250,000
Employee supplemental savings plan assets	27,557,000	31,741,000
Property and equipment—net	22,439,000	25,743,000
Investments	10,853,000	143,000
Other assets	2,636,000	3,741,000
TOTAL ASSETS	1,506,424,000	1,487,402,000
LIABILITIES
Accounts payable and accrued expenses	106,271,000	149,506,000
Accrued salaries and related expenses	60,940,000	57,409,000
Billings in excess of revenue earned	12,685,000	13,408,000
Deferred income taxes—current	0	3,330,000
Total Current Liabilities	179,896,000	223,653,000
Deferred income taxes—non-current	102,035,000	65,103,000
Accrued retirement	29,877,000	32,804,000
Other long-term liabilities	10,879,000	11,063,000
TOTAL LIABILITIES	$ 322,687,000	$ 332,623,000
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY
Additional paid-in capital	$ 438,168,000	$ 428,895,000
Treasury stock	(9,158,000)	(9,158,000)
Retained earnings	754,457,000	734,873,000
Accumulated other comprehensive loss	(109,000)	(207,000)
TOTAL STOCKHOLDERS' EQUITY	1,183,737,000	1,154,779,000
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	1,506,424,000	1,487,402,000
Class A Common Stock [Member]
STOCKHOLDERS' EQUITY
Common stock	247,000	244,000
TOTAL STOCKHOLDERS' EQUITY	247,000	244,000
Class B Common Stock [Member]
STOCKHOLDERS' EQUITY
Common stock	132,000	132,000
TOTAL STOCKHOLDERS' EQUITY	$ 132,000	$ 132,000

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parenthetical - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Treasury Stock, Shares	244,113	244,113
Class A Common Stock [Member]
Common Stock, Par Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	150,000,000	150,000,000
Common Stock, Shares Issued	24,731,584	24,423,514
Common Stock, Shares Outstanding	24,487,471	24,179,401
Class B Common Stock [Member]
Common Stock, Par Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	50,000,000	50,000,000
Common Stock, Shares Issued	13,191,845	13,192,845
Common Stock, Shares Outstanding	13,191,845	13,192,845

Consolidated Statements of Inco

Consolidated Statements of Income and Loss - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
REVENUES	$ 1,550,117,000	$ 1,773,981,000	$ 2,310,072,000
Cost of services	1,320,697,000	1,524,208,000	1,995,630,000
General and administrative expenses	144,534,000	154,957,000	173,772,000
Goodwill impairment	0	0	118,427,000
OPERATING INCOME	84,886,000	94,816,000	22,243,000
Loss on extinguishment of debt	0	(10,074,000)	0
Interest expense	(1,193,000)	(5,802,000)	(16,266,000)
Interest income	160,000	394,000	608,000
Other income (expense), net	1,501,000	(233,000)	(32,000)
INCOME FROM OPERATIONS BEFORE INCOME TAXES AND EQUITY METHOD INVESTMENTS	85,354,000	79,101,000	6,553,000
Provision for income taxes	(34,366,000)	(31,525,000)	(11,842,000)
Equity in gains (losses) of unconsolidated subsidiaries	139,000	(282,000)	(860,000)
NET INCOME (LOSS)	$ 51,127,000	$ 47,294,000	$ (6,149,000)
Class A Common Stock [Member]
BASIC EARNINGS (LOSS) PER SHARE:
Basic earnings (loss) per share	$ 1.36	$ 1.27	$ (0.17)
DILUTED EARNINGS (LOSS) PER SHARE:
Diluted earnings (loss) per share	1.36	1.27	(0.17)
Class B Common Stock [Member]
BASIC EARNINGS (LOSS) PER SHARE:
Basic earnings (loss) per share	1.36	1.27	(0.17)
DILUTED EARNINGS (LOSS) PER SHARE:
Diluted earnings (loss) per share	$ 1.36	$ 1.27	$ (0.17)

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income and Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net income (loss)	$ 51,127	$ 47,294	$ (6,149)
OTHER COMPREHENSIVE INCOME (LOSS):
Actuarial gain (loss) on defined benefit pension plans, net of tax	84	(64)	36
Translation adjustments, net of tax	14	(19)	(15)
Total other comprehensive income (loss)	98	(83)	21
COMPREHENSIVE INCOME (LOSS)	$ 51,225	$ 47,211	$ (6,128)

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($)	Total	Common Stock, Class A	Common Stock, Class B	Additional Paid-In Capital	Treasury Stock, at cost	Retained Earnings	Accumulated Other Comprehensive Loss
At beginning of year at Dec. 31, 2012		$ 241,000	$ 132,000	$ 417,917,000	$ (9,158,000)	$ 756,241,000	$ (145,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises		1,000		1,766,000
Stock compensation expense				5,236,000
Tax deficiency from the exercise of stock options				(2,332,000)
Contribution of Class A common stock to Employee Stock Ownership Plan				1,200,000
Net income (loss)	$ (6,149,000)					(6,149,000)
Dividends						(31,200,000)
Actuarial gain (loss) on defined benefit pension plans, net of tax	36,000						36,000
Translation adjustments, net of tax	(15,000)						(15,000)
At end of year at Dec. 31, 2013	1,133,771,000	242,000	132,000	423,787,000	(9,158,000)	718,892,000	(124,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises		2,000		3,919,000
Stock compensation expense				4,400,000
Tax deficiency from the exercise of stock options				(3,211,000)
Contribution of Class A common stock to Employee Stock Ownership Plan				0
Net income (loss)	47,294,000					47,294,000
Dividends						(31,313,000)
Actuarial gain (loss) on defined benefit pension plans, net of tax	(64,000)						(64,000)
Translation adjustments, net of tax	(19,000)						(19,000)
At end of year at Dec. 31, 2014	1,154,779,000	244,000	132,000	428,895,000	(9,158,000)	734,873,000	(207,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises		3,000		7,865,000
Stock compensation expense				4,379,000
Tax deficiency from the exercise of stock options				(2,971,000)
Contribution of Class A common stock to Employee Stock Ownership Plan				0
Net income (loss)	51,127,000					51,127,000
Dividends						(31,543,000)
Actuarial gain (loss) on defined benefit pension plans, net of tax	84,000						84,000
Translation adjustments, net of tax	14,000						14,000
At end of year at Dec. 31, 2015	$ 1,183,737,000	$ 247,000	$ 132,000	$ 438,168,000	$ (9,158,000)	$ 754,457,000	$ (109,000)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 51,127,000	$ 47,294,000	$ (6,149,000)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Deferred income taxes	30,553,000	18,668,000	(10,915,000)
Depreciation and amortization	30,276,000	30,446,000	30,504,000
Stock-based compensation	4,379,000	4,400,000	5,236,000
Gain on disposition of business	(1,692,000)	0	0
(Gain) loss on sale and retirement of property and equipment	(656,000)	251,000	(402,000)
Equity in (gains) losses of unconsolidated subsidiaries	(139,000)	282,000	860,000
Excess tax benefits from the exercise of stock options	(73,000)	(70,000)	(53,000)
Loss on extinguishment of debt	0	10,074,000	0
Goodwill impairment	0	0	118,427,000
Change in assets and liabilities—net of effects from acquired businesses:
Receivables-net	82,727,000	102,076,000	91,583,000
Prepaid expenses and other	(4,990,000)	326,000	9,334,000
Contractual inventory	0	3,963,000	30,800,000
Employee supplemental savings plan asset	4,184,000	24,000	(4,413,000)
Accounts payable and accrued expenses	(44,103,000)	(87,105,000)	(89,935,000)
Accrued salaries and related expenses	2,703,000	(2,762,000)	3,677,000
Billings in excess of revenue earned	913,000	(750,000)	(1,291,000)
Accrued retirement	(2,927,000)	(761,000)	4,175,000
Other	1,601,000	569,000	6,841,000
Net cash flow from operating activities	153,883,000	126,925,000	188,279,000
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisition of businesses-net of cash acquired	(101,556,000)	(124,247,000)	(11,382,000)
Purchases of property and equipment	(5,202,000)	(4,083,000)	(11,087,000)
Payments to acquire investments	(4,500,000)	(159,000)	(422,000)
Transaction costs for disposition of business	(1,174,000)	0	0
Investment in capitalized software for internal use	(1,025,000)	(7,399,000)	(2,536,000)
Proceeds from sale of property and equipment	696,000	0	402,000
Proceeds from sale of investment	13,000	0	239,000
Net cash flow from investing activities	(112,748,000)	(135,888,000)	(24,786,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings under revolving credit facility	163,200,000	160,000,000	0
Repayments under revolving credit facility	(163,200,000)	(160,000,000)	0
Dividends paid	(31,543,000)	(31,312,000)	(31,208,000)
Proceeds from exercise of stock options	7,868,000	3,922,000	1,767,000
Excess tax benefits from the exercise of stock options	73,000	70,000	53,000
Repayment of senior unsecured notes	0	(207,250,000)	0
Debt issuance costs	0	(1,687,000)	0
Net cash flow from financing activities	(23,602,000)	(236,257,000)	(29,388,000)
NET CHANGE IN CASH AND CASH EQUIVALENTS	17,533,000	(245,220,000)	134,105,000
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	23,781,000	269,001,000	134,896,000
CASH AND CASH EQUIVALENTS, END OF PERIOD	41,314,000	23,781,000	269,001,000
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid for interest	1,203,000	8,597,000	15,903,000
Noncash investing and financing activities:
Capital expenditures incurred but not yet paid	0	96,000	0
Employee Stock Ownership Plan contributions	$ 0	$ 0	$ 1,287,000

Description of the Business (No

Description of the Business (Notes)	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of the Business [Text Block]	Description of the Business ManTech International Corporation (depending on the circumstances, “ManTech” “Company” “we” “our” “ours” or “us”) provides innovative technologies and solutions for mission-critical national security programs for the intelligence community; the departments of Defense, State, Homeland Security, Health and Human Services, Veteran Affairs and Justice, including the Federal Bureau of Investigation (FBI); the space community; and other U.S. government customers. We provide support to critical national security programs for approximately 50 federal agencies through approximately 1,000 current contracts. Our expertise includes cybersecurity; software and systems development; enterprise IT; multi-disciplined intelligence; program protection and mission assurance; systems engineering; test and evaluation (T&E); command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR); training; supply chain management and logistics; and management consulting. We support major national missions, such as military readiness and wellness, terrorist threat detection, information security and border protection. Our employees operate primarily in the United States, as well as numerous locations internationally.

Summary of Significant Accounti

Summary of Significant Accounting Policies (Notes)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	Summary of Significant Accounting Policies Principles of Consolidation -Our consolidated financial statements include the accounts of ManTech International Corporation, subsidiaries we control and variable interest entities that are required to be consolidated. All intercompany accounts and transactions have been eliminated. Investments in entities where we have significant influence, but not control, are accounted for using the equity method. Use of Accounting Estimates -We prepare our consolidated financial statements in conformity with generally accepted accounting principles in the United States of America (GAAP), which require management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. These estimates involve judgments with respect to, among other things, various future economic factors that are difficult to predict and are beyond the control of the Company. Therefore, actual amounts could differ from these estimates. Revenue Recognition -We derive the majority of our revenues from cost-plus-fixed-fee, cost-plus-award-fee, firm-fixed-price or time-and-materials contracts. Revenues for cost-reimbursable contracts are recorded as reimbursable costs are incurred, including an estimated share of the applicable contractual fees earned. For performance-based fees under cost-reimbursable contracts, we recognize the relevant portion of the expected fee to be awarded by the customer at the time such fee can be reasonably estimated, based on factors such as our prior award experience and communications with the customer regarding performance, or upon approval by the customer. For time-and-materials contracts, revenues are recognized to the extent of billable rates times hours delivered plus materials and other reimbursable costs incurred. For long-term fixed-price production contracts, revenues are recognized at a rate per unit as the units are delivered or by other methods to measure services provided. Revenues from other long-term fixed-price contracts are recognized ratably over the contract period or by other appropriate methods to measure services provided. Contract costs are expensed as incurred except for certain limited long-term contracts noted below. For long-term contracts, specifically described in the scope section of Accounting Standards Codification (ASC) 605-35 , Revenue Recognition - Construction-Type and Production-Type Contracts , we apply the percentage of completion method. Under the percentage of completion method, income is recognized at a consistent profit margin over the period of performance based on estimated profit margins at completion of the contract. This method of accounting requires estimating the total revenues and total contract costs at completion of the contract. During the performance of long-term contracts, these estimates are periodically reviewed and revisions are made as required using the cumulative catch-up method of accounting. The impact on revenues and contract profit as a result of these revisions is included in the periods in which the revisions are made. This method can result in the deferral of costs or the deferral of profit on these contracts. Because we assume the risk of performing a fixed-price contract at a set price, the failure to accurately estimate ultimate costs or to control costs during performance of the work could result, and in some instances has resulted, in reduced profits or losses for such contracts. Estimated losses on contracts at completion are recognized when identified. In certain circumstances, revenues are recognized when contract amendments have not been finalized. Cost of Services -Cost of services consists primarily of compensation expenses for program personnel, the fringe benefits associated with this compensation and other direct expenses incurred to complete programs, including cost of materials and subcontract efforts. General and Administrative Expenses- General and administrative expenses include the salaries and wages, plus associated fringe benefits of our employees not performing work directly for customers, and associated facilities costs. Among the functions covered by these costs are corporate business development, bid and proposal, contracts administration, finance and accounting, legal, corporate governance and executive and senior management. In addition, we included stock-based compensation, as well as depreciation and amortization expenses related to the general and administrative function. We classify indirect costs incurred as cost of services and general and administrative expenses in the same manner as such costs are defined in our disclosure statements under U.S. Government Cost Accounting Standards. Effective January 1, 2014, we updated our disclosure statements with the DCMA, resulting in certain costs being classified differently either as cost of services or as general and administrative expenses on a prospective basis. This change has caused a net increase in the reported cost of services and a net decrease in reported general and administrative expenses in 2015 and 2014 as compared to 2013; however, total operating costs were not affected by this change. Cash and Cash Equivalents -For the purpose of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks and short-term investments with maturity dates of three months or less at the date of purchase. Due to the short maturity of cash equivalents, the carrying value on our consolidated balance sheets approximates fair value. Property and Equipment -Property and equipment are recorded at original cost to the Company. Upon sale or retirement, the costs and related accumulated depreciation or amortization are eliminated from the respective accounts and any resulting gain or loss is included in income. Maintenance and repairs are charged to expense as incurred. Depreciation and Amortization Method -Furniture and office equipment are depreciated using the straight-line method with estimated useful lives ranging from one to seven years . Leasehold improvements are amortized using the straight-line method over the term of the lease. Goodwill -The purchase price of an acquired business is allocated to the tangible assets, financial assets and separately recognized intangible assets acquired less liabilities assumed based upon their respective fair values, with the excess recorded as goodwill. We review goodwill at least annually for impairment, or whenever events or circumstances indicate that the carrying value of long-lived assets may not be fully recoverable. Other Intangible Assets -Contract rights and other intangible assets are amortized primarily using the pattern of benefits method over periods ranging from one to twenty-five years . We account for the cost of computer software developed or obtained for internal use in accordance with ASC 350-985 , Intangibles - Goodwill and Other - Software . These capitalized software costs are included in other intangible assets, net. We account for software development costs related to software products for sale, lease or otherwise marketed in accordance with ASC 985-20 , Software - Costs of Software to Be Sold, Leased, or Marketed . For projects fully funded by us, development costs are capitalized from the point of demonstrated technological feasibility until the point in time that the product is available for general release to customers. Once the product is available for general release, capitalized costs are amortized based on units sold or on a straight-line basis over a five -year period or other such shorter period as may be required. Impairment of Long-Lived Assets- Whenever events or changes in circumstances indicate that the carrying amount of long-lived assets may not be fully recoverable, we evaluate the probability that future undiscounted net cash flows will be less than the carrying amount of the assets. If any impairment were indicated as a result of this review, we would recognize a loss based on the amount by which the carrying amount exceeds the estimated fair value. Employee Supplemental Savings Plan Assets -We maintain several non-qualified defined contribution supplemental retirement plans for certain key employees that are accounted for in accordance with ASC 710-10-05 , Compensation - General - Deferred Compensation - Rabbi Trust , as the underlying assets are held in rabbi trusts with investments directed by the respective employee. A rabbi trust is a grantor trust generally set up to fund compensation for a select group of management and the assets of this trust are available to satisfy the claims of general creditors in the event of bankruptcy of the Company. The assets held by the rabbi trusts are recorded at cash surrender value in our consolidated financial statements as Employee Supplemental Savings Plan (ESSP) assets with a related liability to employees recorded as a deferred compensation liability in accrued retirement. We reclassified ESSP assets from the other line item in cash flow from operating activities of the consolidated statement of cash flows for the years ended December 31, 2014 and 2013 to conform with current period presentation. Billings In Excess of Revenue Earned -We receive advances and milestone payments from customers that exceed the revenues earned to date. We classify such items as current liabilities. Stock-based Compensation -We account for stock-based compensation in accordance with ASC 718 , Compensation - Stock Compensation , which requires the use of a valuation model to calculate the fair value of stock-based awards. We have elected to use the Black-Scholes-Merton pricing model to determine fair value on the dates of grant. The fair value is included in operating expenses or capitalized, as appropriate, straight-line over the period in which service is provided in exchange for the award. The grant date fair value of the restricted stock is equal to the closing market price of our common stock on the date of grant. The compensation expense for restricted stock is recognized over the service period and is based on the grant date fair value of the stock and the number of shares expected to vest. The grant date fair value of the restricted stock unit (RSU) is equal to the closing market price of our common stock on the grant date less the present value of dividends expected to be awarded during the service period. We recognize the grant date fair value of RSUs of shares we expect to issue as compensation expense ratably over the requisite service period. Income Taxes -We account for income taxes in accordance with ASC 740 , Income Taxes . Under this method, deferred income taxes are determined based on the estimated future tax effects of differences between the financial statement and tax bases of assets and liabilities given the provisions of enacted tax laws. Deferred income tax provisions and benefits are based on changes to the assets or liabilities from year-to-year. In providing for deferred taxes, we consider tax regulations of the jurisdictions in which we operate, estimates of future taxable income and available tax planning strategies. If tax regulations, operating results or the ability to implement tax-planning strategies vary, adjustments to the carrying value of deferred tax assets and liabilities may be required. Valuation allowances are recorded related to deferred tax assets based on the “more likely than not” criteria. We recognize the financial statement benefit of a tax position only after determining that the relevant tax authority would “more likely than not” sustain the position following an audit. For tax positions meeting the “more likely than not” threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. Due to a change in accounting principle resulting from Accounting Standards Update (ASU) 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, the deferred tax liabilities and assets are classified as noncurrent in our consolidated balance sheet as of December 31, 2015. The prior periods were not retrospectively adjusted. Therefore, the deferred income tax liabilities and assets are classified into current and noncurrent amounts in our consolidated balance sheet as of December 31, 2014. Foreign-Currency Translation -All assets and liabilities of foreign subsidiaries are translated into U.S. dollars at fiscal year-end exchange rates. Income and expense items are translated at average monthly exchange rates prevailing during the fiscal year. The resulting translation adjustments are recorded as a component of accumulated other comprehensive income (loss). Comprehensive Income (Loss) -Comprehensive income (loss) is presented in our consolidated statements of changes in stockholders' equity. Comprehensive income (loss) consists of net income (loss); translation adjustments, net of tax; and actuarial gain (loss) on defined benefit pension plan, net of tax. Fair Value of Financial Instruments -The carrying value of our cash and cash equivalents, accounts receivable, accounts payable and accrued expenses approximate their fair value because of the short-term nature of these amounts. Variable Interest Entities -We determine whether we have a controlling financial interest in a variable interest entity (VIE). The reporting entity with a variable interest or interest that provides the reporting entity with a controlling financial interest in a VIE will have both (a) the power to direct the activities of a VIE that most significantly impact the VIE's economic performance and (b) the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. We have one entity that has been consolidated as a VIE. The purpose of the entity is to perform on certain U.S. Navy contracts. The maximum amount of loss we are exposed to as of December 31, 2015 was not material to our consolidated financial statements. Investments -Investments where we have the ability to exercise significant influence, but we do not control, are accounted for under the equity method of accounting and are included in other assets on our consolidated balance sheets. Significant influence typically exists if we have a 20% to 50% ownership interest in the investee. Under this method of accounting, our share of the net earnings or losses of the investee is included in equity in earnings or losses of unconsolidated subsidiaries on our consolidated statement of income and loss. Investments where we have less than 20% ownership interest in the investee and lack the ability to exercise significant influence are accounted for under the cost method. Under the cost method, we recognize our investment in the stock of an investee as an asset. The investment is measured initially at cost. We recognize as income dividends received that are distributed from net accumulated earnings. Dividends received in excess of earnings are considered a return of investment and are recorded as reductions of costs of the investment. Impairment is assessed at the individual investment level. An investment is impaired if the fair value of the investment is less than its costs. If it is determined that the impairment is other than temporary, then an impairment loss is recognized in earnings. The fair value of the investment would become the new cost basis of the investment and will not be adjusted for subsequent recoveries in fair value. We reclassified investments from the other assets line item on the consolidated balance sheet at December 31, 2014 to conform with the current period presentation. Accounting Standards Updates In November 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes . Prior to this Update, GAAP required an entity to separate deferred income tax liabilities and assets into current and noncurrent amounts in a classified statement of financial position. To simplify the presentation of deferred income taxes, the amendments in this Update require the deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. Noncurrent balance sheet presentation of all deferred taxes eliminates the requirement to allocate a valuation allowance on a pro rata basis between gross current and noncurrent deferred tax assets. The amendments in this Update apply to all entities that present a classified statement of financial position. The current requirement that deferred tax liabilities and assets of a tax-paying component of an entity be offset and presented as a single amount is not affected by the amendments in this Update. For public business entities, the amendments in this Update are effective for financial statements issued for annual periods after December 15, 2016, and interim periods within those annual periods. Earlier application is permitted for all entities as of the beginning of an interim or annual reporting period. The amendments in this Update may be applied either prospectively to all deferred tax liabilities and assets or retrospectively to all periods presented. We adopted ASU 2015-17 as of December 31, 2015 and applied it prospectively. On September 25, 2015, the FASB issued ASU 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement Period Adjustments . The amendments in this Update require that an acquirer recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. The amendments in this Update require that the acquirer record, in the same period’s financial statements, the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The amendments in this Update require an entity to present separately on the face of the income statement or disclose in the notes the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The amendments in this Update are effective for fiscal years beginning after December 15, 2015, including interim periods within those fiscal years. The amendments in this Update should be applied prospectively to adjustments to provisional amounts that occur after the effective date of this Update with earlier application permitted for financial statements that have not been issued. We plan to adopt both of these Updates on January 1, 2016. The adoption of these Updates are not expected to have a material impact on our results of operations, financial position or cash flows. In April 2015, the FASB issued ASU 2015-03, Interest - Imputation of Interest (Subtopic 835-10): Simplifying the Presentation of Debt Issuance Costs. The Update requires debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of the related debt liability instead of being presented as an asset. This Update requires retrospective application and represents a change in accounting principle. This Update is effective for fiscal years beginning after December 15, 2015. Early adoption is permitted for financial statements that have not been previously issued. In August 2015, the FASB issued ASU 2015-15, Interest - Imputation of Interest (Subtopic 835-30). This Update was issued due to the absence of authoritative guidance within update 2015-03 for debt issuance costs related to line-of-credit arrangements. This Update states that the Securities and Exchange Commission (SEC) staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any borrowings on the line-of-credit arrangement. The Update requires retrospective application and represents a change in accounting principle. This Update is effective for fiscal years beginning after December 15, 2015. Early adoption is permitted for financial statements that have not been previously issued. We plan to adopt both of these Updates on January 1, 2016. The adoption of these Updates are not expected to have a material impact on our results of operations, financial position or cash flows. On May 28, 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. ASU 2014-09 supersedes existing revenue recognition guidance, including ASC 605-35 , Revenue Recognition - Construction-Type and Production-Type Contracts . ASU 2014-09 outlines a single set of comprehensive principles for recognizing revenue under GAAP. Among other things, it requires companies to identify contractual performance obligations and determine whether revenue should be recognized at a point in time or over time. These concepts, as well as other aspects of ASU 2014-09, may change the method and/or timing of revenue recognition for certain of our contracts. ASU 2014-09 may be applied either retrospectively or through the use of a modified-retrospective method. In August 2015, the FASB issued ASU 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date. The amendments in ASU 2015-14 defer the effective date of ASU 2014-09 for all entities by one year. Public business entities, certain not-for-profit entities, and certain employee benefit plans should apply the guidance in ASU 2014-09 to annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. We are currently evaluating methods of adoption as well as the effect on our consolidated financial statements. In April 2015, the FASB issued ASU 2015-05, Intangibles - Goodwill and Other - Internal Use Software. ASU 2015-05 will help entities evaluate the accounting for fees paid by a customer in a cloud computing arrangement by providing guidance as to whether an arrangement includes the sale or license of software. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The amendments in this update are effective for interim and annual periods beginning after December 31, 2015. Early adoption is permitted. We plan to adopt this update on January 1, 2016. We will adopt the guidance prospectively to arrangements entered into, or materially modified, after the effective date. The adoption of this Update is not expected to have a material impact on our results of operations, financial position or cash flows. In February 2015, the FASB issued ASU 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis. ASU 2015-02 requires management to evaluate whether limited partnerships and similar legal entities are variable interest entities (VIEs) or voting interest entities. ASU 2015-02 eliminates the presumption that a general partner should consolidate a limited partnership and affects the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships. ASU 2015-02 also provides a scope exception from consolidation guidance for reporting entities with interests in legal entities that are required to comply with or operate in accordance with requirements that are similar to those in Rule 2a-7 of the Investment Company Act of 1940 for registered money market funds. The amendments in this Update are effective for interim and annual periods beginning after December 15, 2015. Early adoption is permitted. A reporting entity may apply the amendments in ASU 2015-02 using: (a) a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the fiscal year of adoption; or (b) by applying the amendments retrospectively. The adoption of this Update is not expected to have a material impact on our results of operations, financial position or cash flows. In January 2015, the FASB issued ASU 2015-01, Income Statement - Extraordinary and Unusual Items (Subtopic 225-20) - Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items , which eliminates from GAAP the concept of extraordinary items. The Board concluded that the amendments in this ASU will not result in a loss of information because although the amendments will eliminate the requirements in Subtopic 225-20 for reporting entities to consider whether an underlying event or transaction is extraordinary, the presentation and disclosure guidance for items that are unusual in nature or occur infrequently will be retained and will be expanded to include items that are both unusual in nature and infrequently occurring. The ASU is effective for annual periods ending after December 15, 2015, and interim periods thereafter. A reporting entity also may apply the amendments retrospectively to all prior periods presented in the financial statements. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The adoption of ASU 2015-01 is not expected to have a material impact on our results of operations, financial position or cash flows. On August 27, 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements - Going Concern , which provides guidance on determining when and how reporting entities must disclose going-concern uncertainties in their financial statements. This Update requires management to perform interim and annual assessments of an entity's ability to continue as a going concern within one year of the date of issuance of an entity's financial statements. Further, an entity must provide certain disclosures if there is substantial doubt about the entity's ability to continue as a going concern. The ASU is effective for annual periods ending after December 15, 2016, and interim periods thereafter; early adoption is permitted. The adoption of ASU 2014-15 is not expected to have a material impact on our results of operations, financial position or cash flows. Other ASUs effective after December 31, 2015 are not expected to have a material effect on our consolidated financial statements.

Acquisitions (Notes)

Acquisitions (Notes)	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Acquisitions [Text Block]	Acquisitions Knowledge Consulting Group, Inc.- On June 15, 2015 , we completed the acquisition of Knowledge Consulting Group, Inc. (KCG). The results of KCG's operations have been included in our condensed consolidated financial statements since that date. The acquisition was completed through an agreement and plan of merger dated June 15, 2015 , by and among ManTech Advanced Systems International, Inc., Knight Acquisitions Corporation and Knowledge Consulting Group, Inc. KCG provides comprehensive cyber security services including cloud security, certification and accreditation and various cyber defense solutions across federal and commercial markets. The acquisition strategically positions us to pursue additional cyber work in the Department of Homeland Security, FBI and the intelligence community by leveraging our enhanced cloud security expertise. We funded the acquisition through a combination of cash on hand and borrowings under our revolving credit facility. The agreement did not contain provisions for contingent consideration. For the year ended December 31, 2015, we incurred approximately $0.3 million of acquisition costs related to the KCG transaction, which are included in the general and administrative expenses in our consolidated statement of income. The purchase price of $68.2 million was allocated to the underlying assets and liabilities based on their estimated fair value at the date of acquisition. The goodwill recorded related to this transaction will be deductible for tax purposes over 15 years , assuming adequate levels of taxable income. Recognition of goodwill is largely attributed to the value paid for KCG's capabilities in providing comprehensive cyber security services throughout the Department of Defense (DoD) and intelligence community. In allocating the purchase price, we considered among other factors analysis of historical financial performance and estimates of future performance of KCG's contracts. The components of other intangible assets associated with the acquisition were customer relationships and backlog valued at $12.4 million and $0.8 million , respectively. Customer contracts and related relationships represent the underlying relationships and agreements with KCG's existing customers. Customer relationships are amortized using the pattern of benefits method over their estimated useful lives of approximately 15 years . Backlog is amortized straight-line over its estimated useful life of 1 year . The weighted-average amortization period for the intangible assets is 14 years . The following table represents the purchase price allocation for KCG (in thousands): Knowledge Consulting Group, Inc. Cash and cash equivalents $ 658 Receivables 6,532 Prepaid expenses and other 460 Goodwill 47,487 Other intangible assets 13,219 Property and equipment 1,419 Investments 15 Other assets 31 Accounts payable and accrued expenses (1,269 ) Accrued salaries and related expenses (336 ) Billings in excess of revenue earned (2 ) Net assets acquired and liabilities assumed $ 68,214 We have not disclosed current period, nor pro forma revenues and earnings attributable to KCG as our integration of these operations post-acquisition and the entity's accounting methods pre-acquisition make it impracticable. Welkin Associates, Ltd.- On April 27, 2015 , we completed the acquisition of Welkin Associates, Ltd. (Welkin) formerly a wholly-owned subsidiary of Computer Sciences Corporation (CSC). The results of Welkin's operations have been included in our condensed consolidated financial statements since that date. The acquisition was completed through a stock purchase agreement dated April 27, 2015 , by and among ManTech International Corporation, CSC and Welkin Associates, Ltd. Welkin delivers mission-centric services in high-end systems engineering and advanced national security technology and business services. The acquisition strategically positions us to pursue large engineering and support opportunities throughout the intelligence community and DoD. We funded the acquisition with cash on hand. The stock purchase agreement did not contain provisions for contingent consideration. For the year ended December 31, 2015, we incurred approximately $0.7 million of acquisition costs related to the Welkin transaction, which are included in the general and administrative expenses in our consolidated statement of income. The purchase price of $34.0 million was allocated to the underlying assets and liabilities based on their estimated fair value at the date of acquisition. The goodwill recorded related to this transaction will be deductible for tax purposes over 15 years , assuming adequate levels of taxable income. Recognition of goodwill is largely attributed to the value paid for Welkin's capabilities in providing high-end systems engineering and support services throughout the intelligence community and DoD. In allocating the purchase price, we considered among other factors, analysis of historical financial performance and estimates of future performance of Welkin's contracts. The components of other intangible assets associated with the acquisition were customer relationships and backlog valued at $6.0 million and $0.4 million , respectively. Customer contracts and related relationships represent the underlying relationships and agreements with Welkin's existing customers. Customer relationships are amortized using the pattern of benefits method over their estimated useful lives of approximately 15 years . Backlog is amortized straight-line over its estimated useful life of 1 year . The weighted-average amortization period for the intangible assets is 14 years . The following table represents the purchase price allocation for Welkin (in thousands): Welkin Associates, Ltd. Receivables $ 3,901 Prepaid expenses and other 141 Goodwill 24,436 Other intangible assets 6,350 Property and equipment 100 Accounts payable and accrued expenses (436 ) Accrued salaries and related expenses (492 ) Net assets acquired and liabilities assumed $ 34,000 We have not disclosed current period, nor pro forma, revenues and earnings attributable to Welkin as our integration of these operations post-acquisition and the entity's accounting methods pre-acquisition make it impracticable. 7Delta Inc. -On May 23, 2014 , we completed the acquisition of all equity interests in 7Delta Inc. (7Delta). The results of 7Delta's operations have been included in our consolidated financial statements since that date. The acquisition was completed through a stock purchase agreement dated May 23, 2014 , by and among ManTech International Corporation, 7Delta, SLS Holdings, Inc. and the stockholders of SLS Holdings, Inc. 7Delta performs critical services such as applications and software development, program management, systems integration, information assurance and security architecture primarily within the healthcare community at the Department of Veteran Affairs. We funded the acquisition through a combination of cash on hand and borrowings under our revolving credit facility. The stock purchase agreement did not contain provisions for contingent consideration. For the year ended December 31, 2014, ManTech incurred approximately $0.5 million of acquisition costs related to the 7Delta transaction, which are included in the general and administrative expenses in our consolidated statement of income. The purchase price of $81.4 million was allocated to the underlying assets and liabilities based on their estimated fair value at the date of acquisition. The goodwill recorded related to this transaction will be deductible for tax purposes over 15 years , assuming adequate levels of taxable income. Recognition of goodwill is largely attributed to the value paid for 7Delta's capabilities in providing software development, program management, system integration, information assurance and security architecture to the Department of Veteran Affairs. In allocating the purchase price, we considered among other factors, analysis of historical financial performance and estimates of future performance of 7Delta's contracts. The components of other intangible assets associated with the acquisition were customer relationships and backlog valued at $4.8 million and $2.9 million , respectively. Customer contracts and related relationships represent the underlying relationships and agreements with 7Delta's existing customers. Customer relationships are amortized using the pattern of benefits method over their estimated useful lives of approximately 10 years . Backlog is amortized straight-line over its estimated useful life of 2 years . The weighted-average amortization period for the intangible assets is 7 years . The following table represents the purchase price allocation for 7Delta (in thousands): 7Delta Inc. Cash and cash equivalents $ 1,408 Receivables 9,664 Prepaid expenses and other 175 Goodwill 69,967 Other intangible assets 7,762 Property and equipment 597 Other assets 39 Accounts payable and accrued expenses (6,617 ) Accrued salaries and related expenses (1,399 ) Billings in excess of revenue earned (229 ) Net assets acquired and liabilities assumed $ 81,367 We have not disclosed current period, nor pro forma, revenues and earnings attributable to 7Delta as our integration of these operations post acquisition and the entity's accounting methods preacquisition make it impracticable. Allied Technology Group, Inc. -On February 18, 2014 , we completed the acquisition of all equity interests in Allied Technology Group, Inc. (ATG). The results of ATG's operations have been included in our consolidated financial statements since that date. The acquisition was completed through a stock purchase agreement dated February 18, 2014 , by and among ManTech Advanced Systems International, Inc., Allied Technology Group, Inc. and the stockholders of ATG. ATG is an innovative engineering and information management solution company with strong customer relationships and strategic contracts with the Department of Homeland Security. ATG provides IT, engineering services, program management and training solutions to a variety of federal customers. The acquisition will enable us to deliver services through their unrestricted prime position on the Department of Homeland Security's primary acquisition vehicles: Technical, Acquisition and Business Support Services and Enterprise Acquisition Gateway for Leading Edge Solutions II. We funded the acquisition with cash on hand. The stock purchase agreement did not contain provisions for contingent consideration. For the year ended December 31, 2014, ManTech incurred approximately $0.4 million of acquisition costs related to the ATG transaction, which are included in the general and administrative expenses in our consolidated statement of income. The purchase price of $45.0 million was allocated to the underlying assets and liabilities based on their estimated fair value at the date of acquisition. The goodwill recorded related to this transaction will be deductible for tax purposes over 15 years , assuming adequate levels of taxable income. Recognition of goodwill is largely attributed to the value paid for ATG's capabilities in providing technology service program management, systems engineering and IT services to the Department of Homeland Security. In allocating the purchase price, we considered among other factors, analysis of historical financial performance and estimates of future performance of ATG's contracts. The components of other intangible assets associated with the acquisition were customer relationships and backlog valued at $6.4 million and $0.6 million , respectively. Customer contracts and related relationships represent the underlying relationships and agreements with ATG's existing customers. Customer relationships are amortized using the pattern of benefits method over their estimated useful lives of approximately 20 years . Backlog is amortized straight-line over its estimated useful life of 1 year . The weighted-average amortization period for the intangible assets is 18 years . The following table represents the purchase price allocation for ATG (in thousands): Allied Technology Group, Inc. Cash and cash equivalents $ 712 Receivables 11,670 Prepaid expenses and other 1,432 Contractual inventory 1 Goodwill 28,806 Other intangible assets 7,071 Property and equipment 899 Other assets 111 Accounts payable and accrued expenses (3,399 ) Accrued salaries and related expenses (2,155 ) Billings in excess of revenue earned (148 ) Net assets acquired and liabilities assumed $ 45,000 We have not disclosed current period, nor pro forma, revenues and earnings attributable to ATG as our integration of these operations post acquisition and the entity's accounting methods preacquisition make it impracticable. ALTA Systems, Inc. -On January 8, 2013 , we completed the acquisition of ALTA Systems, Inc. (ALTA). The results of ALTA's operations have been included in our consolidated financial statements since that date. The acquisition was completed through a stock purchase agreement dated January 8, 2013 , by and among ManTech International Corporation, ALTA Holdings LLC and the sole member of ALTA Holding LLC. ALTA is an IT and professional services company with valuable applications in healthcare systems and capital planning. ALTA provides a broad range of IT and professional services to government and private industry in three major areas: capital planning and investment control; system design, development and operations; and fraud detection and statistical analysis. The acquisition allows ManTech to deliver technology services through ALTA's prime position on the Centers of Medicare and Medicaid Services Enterprise Systems Development contract. ManTech funded the acquisition with cash on hand. The stock purchase agreement did not contain provisions for contingent consideration. For the year ended December 31, 2013, ManTech incurred approximately $0.1 million of acquisition costs related to the ALTA transaction, which are included in the general and administrative expenses in our consolidated statement of loss. The purchase price of $10.2 million was allocated to the underlying assets and liabilities based on their estimated fair value at the date of acquisition. We have recorded total assets of $11.1 million , including goodwill and intangible assets recognized in connection with the acquisition, and total liabilities of $0.9 million . Included in total assets were $0.7 million in acquisition related intangible assets. We recorded goodwill of $9.1 million , which will be deductible for tax purposes over 15 years , assuming adequate levels of taxable income. Recognition of goodwill is largely attributed to the value paid for ALTA's capabilities in providing technology services to the U.S. government in the health care sector. In allocating the purchase price, we considered among other factors, analysis of historical financial performance and estimates of future performance of ALTA's contracts. The components of other intangible assets associated with the acquisition were customer relationships and backlog valued at $0.6 million and $0.1 million , respectively. Customer contracts and related relationships represent the underlying relationships and agreements with ALTA's existing customers. Customer relationships and backlog are amortized straight-line over their estimated useful lives of approximately 20 years and 1 year , respectively. The weighted-average amortization period for the intangible assets is 17 years . We have not disclosed current period, nor pro forma, revenues and earnings attributable to ALTA as our integration of these operations post acquisition and the entity's accounting methods preacquisition make it impracticable.

Earnings (Loss) per Share (Note

Earnings (Loss) per Share (Notes)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Earnings (Loss) Per Share [Text Block]	Earnings (Loss) per Share Under ASC 260 , Earnings per Share , the two-class method is an earnings (loss) allocation formula that determines earnings (loss) per share for each class of common stock according to dividends declared (or accumulated) and participation rights in undistributed earnings (loss). Under that method, basic and diluted earnings (loss) per share data are presented for each class of common stock. In applying the two-class method, we determined that undistributed earnings (loss) should be allocated equally on a per share basis between Class A and Class B common stock. Under our Certificate of Incorporation, the holders of the common stock are entitled to participate ratably, on a share-for-share basis as if all shares of common stock were of a single class, in such dividends, as may be declared by the Board of Directors. During the years ended December 31, 2015 , 2014 and 2013 , we declared and paid quarterly dividends, each in the amount of $0.21 per share on both classes of common stock. Basic earnings (loss) per share has been computed by dividing net income (loss) available to common stockholders by the weighted average number of shares of common stock outstanding during each period. Shares issued during the period and shares reacquired during the period are weighted for the portion of the period in which the shares were outstanding. Diluted earnings (loss) per share have been computed in a manner consistent with that of basic earnings (loss) per share while giving effect to all potentially dilutive common shares that were outstanding during each period. The net income (loss) available to common stockholders and weighted average number of common shares outstanding used to compute basic and diluted earnings (loss) per share for each class of common stock are as follows (in thousands, except per share amounts): Year Ended 2015 2014 2013 Distributed earnings $ 31,543 $ 31,313 $ 31,200 Undistributed earnings (loss) 19,584 15,981 (37,349 ) Net income (loss) $ 51,127 $ 47,294 $ (6,149 ) Class A common stock: Basic net income (loss) available to common stockholders $ 33,145 $ 30,539 $ (3,963 ) Basic weighted average common shares outstanding 24,317 24,047 23,913 Basic earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Diluted net income (loss) available to common stockholders $ 33,197 $ 30,571 $ (3,963 ) Effect of potential exercise of stock options 109 70 — Diluted weighted average common shares outstanding 24,426 24,117 23,913 Diluted earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Class B common stock: Basic net income (loss) available to common stockholders $ 17,982 $ 16,755 $ (2,186 ) Basic weighted average common shares outstanding 13,193 13,193 13,193 Basic earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Diluted net income (loss) available to common stockholders $ 17,930 $ 16,723 $ (2,186 ) Effect of potential exercise of stock options — — — Diluted weighted average common shares outstanding 13,193 13,193 13,193 Diluted earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) For the years ended December 31, 2015 , 2014 and 2013 , options to purchase 1.8 million , 2.7 million and 3.2 million shares, respectively, were outstanding but not included in the computation of diluted earnings (loss) per share because the options' effect would have been anti-dilutive. For the years ended December 31, 2015 , 2014 and 2013 , there were 284,320 shares, 158,371 shares, and 79,567 shares, respectively, issued from the exercise of stock options.

Receivables (Notes)

Receivables (Notes)	12 Months Ended
	Dec. 31, 2015
Receivables [Abstract]
Receivables [Text Block]	Receivables We deliver a broad array of IT and technical services solutions under contracts with the U.S. government, state and local governments and commercial customers. The components of contract receivables are as follows (in thousands): December 31, 2015 2014 Billed receivables $ 233,735 $ 319,065 Unbilled receivables: Amounts billable 47,900 50,393 Revenues recorded in excess of funding 19,213 13,082 Retainage 11,878 4,446 Allowance for doubtful accounts (8,473 ) (9,830 ) Receivables-net $ 304,253 $ 377,156 Amounts billable consist principally of amounts to be billed within the next month. Revenues recorded in excess of funding are billable upon receipt of contractual amendments or other modifications. The retainage is billable upon completion of the contract performance and approval of final indirect expense rates by the government. Accounts receivable at December 31, 2015 are expected to be substantially collected within one year except for approximately $0.6 million , of which 88.9% is related to receivables from sales to the U.S. government. The remainder is related to receivables from contracts in which we acted as a subcontractor to other contractors. The Company does not believe it has significant exposure to credit risk as accounts receivable and the related unbilled amounts are primarily due from the U.S. government. The allowance for doubtful accounts represents our estimate for exposure to compliance, contractual issues and bad debts related to prime contractors.

Property and Equipment (Notes)

Property and Equipment (Notes)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment [Text Block]	Property and Equipment Major classes of property and equipment are summarized as follows (in thousands): December 31, 2015 2014 Furniture and equipment $ 44,718 $ 43,659 Leasehold improvements 35,733 35,601 Property and equipment-gross 80,451 79,260 Accumulated depreciation and amortization (58,012 ) (53,517 ) Property and equipment-net $ 22,439 $ 25,743 Depreciation and amortization expense related to property and equipment for the years ended December 31, 2015 , 2014 and 2013 was $8.5 million , $9.0 million and $8.7 million , respectively.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets (Notes)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets Disclosure [Text Block]	Goodwill and Other Intangible Assets Under ASC 350 , Intangibles - Goodwill and Other , goodwill is to be reviewed at least annually for impairment and whenever events or circumstances indicate that the carrying value of goodwill may not be fully recoverable. We have elected to perform this review during the fourth quarter of each calendar year. In reviewing goodwill for impairment, we have the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the estimated fair value of a reporting unit is less than its carrying amount. If we elect to perform a qualitative assessment and determine that an impairment is more likely than not, the entity is then required to perform the existing two-step quantitative impairment test (described below), otherwise no further analysis is required. We also may elect not to perform the qualitative assessment and, instead, proceed directly to the two-step quantitative impairment test. The goodwill impairment test is a two-step process performed at the reporting unit level. The first step of the goodwill impairment test compares the fair value of a reporting unit with its carrying amount (including goodwill). If the reporting unit's fair value exceeds its carrying value, no further procedures are required. However, if the reporting unit's fair value is less than its carrying value, an impairment of goodwill may exist, requiring a second step to be performed. Step two of this test measures the amount of the impairment loss, if any. Step two of this test requires the allocation of the reporting unit's fair value to its assets and liabilities, including any unrecognized intangible assets, in a hypothetical analysis that calculates the implied fair value of goodwill as if the reporting unit were being acquired in a business combination. If the implied fair value of goodwill is less than the carrying value, the difference is recorded as a goodwill impairment charge in operations. The fair values of the reporting units are determined based on a weighting of the income approach, market approach and market transaction approach. The income approach is a valuation technique in which fair value is based from forecasted future cash flow discounted at the appropriate rate of return commensurate with the risk as well as current rates of return for equity and debt capital as of the valuation date. The forecast used in our estimation of fair value was developed by management based on a contract basis, incorporating adjustments to reflect known contract and market considerations (such as reductions and uncertainty in government spending, pricing pressure and opportunities). The discount rate utilizes a risk adjusted weighted average cost of capital. The market approach is a valuation technique in which the fair value is calculated based on market prices realized in an actual arm's length transaction. The technique consists of undertaking a detailed market analysis of publicly traded companies that provides a reasonable basis for comparison to the Company. Valuation ratios, which relate market prices to selected financial statistics derived from comparable companies, are selected and applied to the Company after consideration of adjustments for financial position, growth, market, profitability and other factors. The market transaction approach is a valuation technique in which the fair value is calculated based on market prices realized in actual arm's length transactions. The technique consists of undertaking a detailed market analysis of merged and acquired companies that provided a reasonable basis for comparison to the Company. Valuation ratios, which relate market prices to selected financial statistics derived from comparable companies, are selected and applied to the Company after consideration of adjustments for financial position, growth, market, profitability and other factors. To assess the reasonableness of the calculated reporting unit fair values, we compare the sum of the reporting units' fair values to the Company's market capitalization (per share stock price times the number of shares outstanding) and calculate an implied control premium (the excess of the sum of the reporting units' fair values over the market capitalization) and then assess the reasonableness of our implied control premium. The changes in the carrying amounts of goodwill during fiscal years 2015 and 2014 were as follows (in thousands): Goodwill Balance Goodwill at December 31, 2013 $ 752,867 Acquisitions 98,773 Goodwill at December 31, 2014 851,640 Acquisitions 71,922 Divestiture (3,971 ) Goodwill at December 31, 2015 $ 919,591 Other intangible assets consisted of the following (in thousands): December 31, 2015 December 31, 2014 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Other intangible assets: Contract and program intangible assets $ 281,682 $ 140,163 $ 141,519 $ 266,272 $ 126,619 $ 139,653 Capitalized software cost for internal use 36,170 23,522 12,648 35,036 19,500 15,536 Other 58 49 9 115 54 61 Total other intangible assets-net $ 317,910 $ 163,734 $ 154,176 $ 301,423 $ 146,173 $ 155,250 Amortization expense relating to intangible assets for the years ended December 31, 2015 , 2014 and 2013 was $21.2 million , $20.4 million and $20.4 million , respectively. We estimate that we will have the following amortization expense for the future periods indicated below (in thousands): Year ending: December 31, 2016 $ 21,484 December 31, 2017 $ 20,018 December 31, 2018 $ 18,314 December 31, 2019 $ 15,836 December 31, 2020 $ 12,614

Debt (Notes)

Debt (Notes)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Debt Disclosure [Text Block]	Debt Revolving Credit Facility -We maintain a credit agreement with a syndicate of lenders led by Bank of America, N.A., as sole administrative agent. The credit agreement provides for a $500 million revolving credit facility, with a $25 million letter of credit sublimit and a $30 million swing line loan sublimit. The credit agreement also includes an accordion feature that permits the Company to arrange with the lenders for the provision of additional commitments. On June 13, 2014, we amended and restated the credit agreement, and extended the maturity date to June 13, 2019 . We deferred $3.4 million in debt issuance costs, cumulatively over the agreements, which are amortized over the term of the amended and restated credit agreement. Borrowings under our credit agreement are collateralized by substantially all the assets of ManTech and its Material Subsidiaries (as defined in the credit agreement) and bear interest at one of the following variable rates as selected by the Company at the time of borrowing: a LIBOR based rate plus market spreads ( 1.25% to 2.25% based on our consolidated total leverage ratio) or Bank of America's base rate plus market spreads ( 0.25% to 1.25% based on our consolidated total leverage ratio). The aggregate annual weighted average interest rates were 1.88% and 0.76% for the years ended December 31, 2015 and 2014 , respectively. The terms of the credit agreement permit prepayment and termination of the loan commitments at any time, subject to certain conditions. The credit agreement requires the Company to comply with specified financial covenants, including the maintenance of certain leverage ratios and a certain consolidated coverage ratio. The credit agreement also contains various covenants, including affirmative covenants with respect to certain reporting requirements and maintaining certain business activities, and negative covenants that, among other things, may limit or impose restrictions on our ability to incur liens, incur additional indebtedness, make investments, make acquisitions and undertake certain other actions. As of, and during, December 31, 2015 and 2014 , we were in compliance with our financial covenants under the credit agreement. There was no outstanding balance on our revolving credit facility at both December 31, 2015 and 2014 . The weighted average borrowings under the revolving portion of the facility during the years ended December 31, 2015 and 2014 were $11.1 million and $9.1 million , respectively. The maximum available borrowing under the revolving credit facility at December 31, 2015 was $480.8 million . At December 31, 2015 and 2014 , we were contingently liable under letters of credit totaling $19.2 million and $0.8 million , respectively, which reduces our availability to borrow under our revolving credit facility. 7.25% Senior Unsecured Notes -On April 15, 2014 , we paid the redemption price plus accrued and unpaid interest on our 7.25% senior unsecured notes issued on April 13, 2010 for $200.0 million , which were registered under the Securities Act of 1933. The 7.25% senior unsecured notes were redeemed at a redemption price of 103.625% of the principal amount of the outstanding 7.25% senior unsecured notes, or $207.3 million . As a result of the redemption of our 7.25% senior unsecured notes, we recorded a loss on the extinguishment of debt for $10.1 million as non-operating income on our consolidated statement of income during the year ended December 31, 2014.

Commitments and Contingencies (

Commitments and Contingencies (Notes)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Commitments and Contingencies Contracts with the U.S. government including subcontracts are subject to extensive legal and regulatory requirements and, from time-to-time, agencies of the U.S. government, in the ordinary course of business, investigate whether our operations are conducted in accordance with these requirements and the terms of the relevant contracts. U.S. government investigations of the Company, whether related to our U.S. government contracts or conducted for other reasons, could result in administrative, civil or criminal liabilities, including repayments, fines or penalties being imposed upon the Company, or could lead to suspension or debarment from future U.S. government contracting. Management believes it has adequately reserved for any losses that may be experienced from any investigation of which it is aware. The Defense Contract Audit Agency (DCAA) has substantially completed our incurred cost audits through 2011 , with no material adjustments. The remaining audits for 2010 through 2015 are not expected to have a material effect on our financial position, results of operations or cash flow and management believes it has adequately reserved for any losses. In the normal course of business, we are involved in certain governmental and legal proceedings, claims and disputes and have litigation pending under several suits. We believe that the ultimate resolution of these matters will not have a material effect on our financial position, results of operations or cash flows. We have an outstanding performance bond in the amount of $19.0 million , which is in connection with a joint venture between ManTech MENA, LLC and Jadwalean International Operations and Management Company in order to fulfill technical support requirements for the Royal Saudi Air Force. We lease office space and equipment under long-term operating leases. A number of the leases contain renewal options and escalation clauses. At December 31, 2015 , aggregate future minimum rental commitments under these leases are as follows (in thousands): Total Year ending: December 31, 2016 $ 30,202 December 31, 2017 25,643 December 31, 2018 22,740 December 31, 2019 21,560 December 31, 2020 15,501 Thereafter 40,255 Total $ 155,901 Office space and equipment rent expense totaled approximately $37.2 million , $42.9 million and $47.6 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. We had $11.1 million of deferred rent liabilities resulting from recording rent expense on a straight-line basis over the life of the respective lease for both the years ended December 31, 2015 and 2014 .

Stockholders Equity and Stock-B

Stockholders Equity and Stock-Based Compensation (Notes)	12 Months Ended
	Dec. 31, 2015
Stockholders Equity and Stock-Based Compensation [Abstract]
Stockholders Equity and Stock-Based Compensation [Text Block]	Stockholders' Equity and Stock-Based Compensation Common Stock -We have 150,000,000 shares of authorized Class A common stock, par value $0.01 per share. We have 50,000,000 shares of authorized Class B common stock, par value $0.01 per share. On December 31, 2015 , there were 24,487,471 shares of Class A common stock outstanding, 244,113 shares of Class A common stock recorded as treasury stock and 13,191,845 shares of Class B common stock outstanding. Holders of Class A common stock are entitled to one vote for each share held of record and holders of Class B common stock are entitled to ten votes for each share held of record, except with respect to any “going private transaction” (generally, a transaction in which George J. Pedersen (our Chairman of the Board and Chief Executive Officer), his affiliates, his direct and indirect permitted transferees or a group, generally including Mr. Pedersen, such affiliates and permitted transferees, seek to buy all outstanding shares), as to which each share of Class A common stock and Class B common stock are entitled to one vote per share. The Class A common stock and the Class B common stock vote together as a single class on all matters submitted to a vote of stockholders, including the election of directors, except as required by law. Holders of common stock do not have cumulative voting rights in the election of directors. Stockholders are entitled to receive, when and if declared by the Board of Directors from time-to-time, such dividends and other distributions in cash, stock or property from our assets or funds legally and contractually available for such purposes subject to any dividend preferences that may be attributable to preferred stock that may be authorized. Each share of Class A common stock and Class B common stock is equal in respect of dividends and other distributions in cash, stock or property, except that in the case of stock dividends, only shares of Class A common stock will be distributed with respect to the Class A common stock and only shares of Class B common stock will be distributed with respect to Class B common stock. In no event will either Class A common stock or Class B common stock be split, divided or combined unless the other class is proportionately split, divided or combined. The shares of Class A common stock are not convertible into any other series or class of securities. Each share of Class B common stock, however, is freely convertible into one share of Class A common stock at the option of the Class B stockholder. Upon the death or permanent mental incapacity of Mr. Pedersen, all outstanding shares of Class B common stock automatically convert to Class A common stock. Preferred Stock -We are authorized to issue an aggregate of 20,000,000 shares of preferred stock, $0.01 par value per share, the terms and conditions of which are determined by our Board of Directors upon issuance. The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of holders of any shares of preferred stock that we may designate and issue in the future. At December 31, 2015 and 2014 , no shares of preferred stock were outstanding and the Board of Directors currently has no plans to issue a series of preferred stock. Accounting for Stock-Based Compensation: Our 2011 Management Incentive Plan (the Plan) was designed to attract, retain and motivate key employees. The types of awards available include options, restricted stock and RSUs. Awards granted under the Plan are settled in shares of Class A common stock. At the beginning of each year, the Plan provides that the number of shares available for issuance automatically increases by an amount equal to 1.5% of the total number of shares of Class A and Class B common stock outstanding on December 31st of the previous year. On January 4, 2016 , there were 565,190 additional shares made available for issuance under the Plan. Through December 31, 2015 , the Board of Directors has authorized the issuance of up to 12,817,107 shares under this plan. Through December 31, 2015 , the remaining aggregate number of shares of our common stock available for future grants under the Plan was 5,059,953 . The Plan expires in May 2021 . The Plan is administered by the compensation committee of our Board of Directors, along with its delegates. Subject to the express provisions of the Plan, the committee has the Board of Directors' authority to administer and interpret the Plan, including the discretion to determine the exercise price, vesting schedule, contractual life and the number of shares to be issued. Stock Compensation Expense -For the years ended December 31, 2015 , 2014 and 2013 , we recorded $4.4 million , $4.4 million and $5.2 million of stock-based compensation expense, respectively. No compensation expense of employees with stock awards, including stock-based compensation expense, was capitalized during the periods. For the years ended December 31, 2015 , 2014 and 2013 , the total recognized tax deficiency from the exercise of stock options, vested cancellations and the vesting of restricted stock was $3.0 million , $3.2 million and $2.3 million , respectively. Stock Options- We typically issue options that vest over three years in equal installments beginning on the first anniversary of the date of grant. Under the terms of the Plan, the contractual life of the option grants may not exceed eight years . During the years ended December 31, 2015 , 2014 and 2013 , we issued options that expire five years from the date of grant. Fair Value Determination -We have used the Black-Scholes-Merton option pricing model to determine fair value of our awards on date of grant. We will reconsider the use of the Black-Scholes-Merton model if additional information becomes available in the future that indicates another model would be more appropriate or if grants issued in future periods have characteristics that cannot be reasonably estimated under this model. The following weighted-average assumptions were used for option grants during the years ended December 31, 2015 , 2014 and 2013 : Volatility -The expected volatility of the options granted was estimated based upon historical volatility of our share price through weekly observations of our trading history. Expected Term -The expected term of options granted to employees during fiscal years 2015 , 2014 and 2013 was determined from historical exercises of the grantee population. For all grants valued during fiscal years 2015 , 2014 and 2013 , the options had graded vesting over three years in equal installments beginning on the first anniversary of the date of the grant and a contractual term of five years . Risk-free Interest Rate -The yield on zero-coupon U.S. Treasury strips was used to extrapolate a forward-yield curve. This “term structure” of future interest rates was then input into a numeric model to provide the equivalent risk-free rate to be used in the Black-Scholes-Merton model based on the expected term of the underlying grants. Dividend Yield -The Black-Scholes-Merton valuation model requires an expected dividend yield as an input. We have calculated our expected dividend yield based on an expected annual cash dividend of $0.84 per share. The following table summarizes weighted-average assumptions used in our calculations of fair value for the years ended December 31, 2015 , 2014 and 2013 : Year Ended 2015 2014 2013 Volatility 26.16 % 28.96 % 31.92 % Expected life of options 3 years 3 years 3 years Risk-free interest rate 1.15 % 0.96 % 0.56 % Dividend yield 3.00 % 3.00 % 3.00 % Stock Option Activity -The weighted-average fair value of options granted during the years ended December 31, 2015 , 2014 and 2013 , as determined under the Black-Scholes-Merton valuation model, was $4.59 , $4.76 and $4.84 , respectively. Option grants that vested during the years ended December 31, 2015 , 2014 and 2013 had a combined fair value of $3.6 million , $4.4 million and $6.1 million , respectively. The following table summarizes stock option activity for the years ended December 31, 2015 , 2014 and 2013 : Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value Stock options at December 31, 2012 3,421,196 $ 38.61 $ 626 Granted 957,525 $ 27.42 Exercised (79,567 ) $ 22.75 $ 400 Cancelled and expired (899,034 ) $ 39.84 Stock options at December 31, 2013 3,400,120 $ 35.51 $ 4,488 Granted 946,576 $ 29.12 Exercised (158,371 ) $ 24.78 $ 754 Cancelled and expired (797,293 ) $ 41.75 Stock options at December 31, 2014 3,391,032 $ 32.76 $ 4,722 Granted 237,853 $ 30.87 Exercised (284,320 ) $ 27.51 $ 1,348 Cancelled and expired (849,255 ) $ 39.56 Stock options at December 31, 2015 2,495,310 $ 30.86 $ 3,583 The following table summarizes non-vested stock options for the year ended December 31, 2015 : Number of Shares Weighted Average Fair Value Non-vested stock options at December 31, 2014 1,673,528 $ 4.83 Granted 237,853 $ 4.59 Vested (726,750 ) $ 4.89 Cancelled (193,341 ) $ 4.79 Non-vested stock options at December 31, 2015 991,290 $ 4.74 The following table includes information concerning stock options exercisable and stock options expected to vest at December 31, 2015 : Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Aggregate Intrinsic Value Stock options exercisable 1,504,020 2 years $ 32.01 $ 2,236 Stock options expected to vest 894,966 4 years $ 29.08 $ 1,242 Stock options exercisable and expected to vest 2,398,986 Unrecognized compensation expense related to outstanding stock options expected to vest as of December 31, 2015 was $3.0 million , which is expected to be recognized over a weighted-average period of 2 years and will be adjusted for any future changes in estimated forfeitures. Restricted Stock -Under the Plan, we have issued restricted stock. A restricted stock award is an issuance of shares that cannot be sold or transferred by the recipient until the vesting period lapses. Restricted stock issued to members of our Board of Directors vest in one year . The related compensation expense is recognized over the service period and is based on the grant date fair value of the stock and the number of shares expected to vest. The grant date fair value of the restricted stock is equal to the closing market price of our common stock on the date of grant. Restricted Stock Activity -The following table summarizes the restricted stock activity during the years ended December 31, 2014 and 2015 : Number of Shares Weighted Average Fair Value Non-vested restricted stock at December 31, 2013 21,000 $ 27.65 Granted 21,000 $ 30.61 Vested (21,000 ) $ 27.65 Non-vested restricted stock at December 31, 2014 21,000 $ 30.61 Granted 21,000 $ 28.98 Vested (21,000 ) $ 30.61 Non-vested restricted stock at December 31, 2015 21,000 $ 28.98 Restricted Stock Units- Under the Plan, we issued restricted stock units (RSUs). RSUs are not actual shares, but rather a right to receive shares in the future based on the level of achievement of performance criteria. The shares are not issued and the employee cannot sell or transfer shares prior to vesting and has no voting rights until the RSUs vest. Employees who are granted RSUs do not receive dividend payments during the service period. The employees' RSUs will result in the delivery of shares if (a) performance criteria is met and (b) the employee remains employed, in good standing, through the date of the performance period. The performance period is 2 years (January 1, 2015 - December 31, 2016). The grant date fair value of the RSUs is equal to the closing market price of our common stock on the grant date less the present value of dividends expected to be awarded during the service period. We recognize the grant date fair value of RSUs of shares we expect to issue as compensation expense ratably over the requisite service period. Restricted Stock Unit Activity- The following table summarizes the nonvested restricted stock unit activity during the year ended December 31, 2015. There was no restricted stock unit activity during the year ended December 31, 2014. Number of Units Weighted Average Fair Value Non-vested restricted stock units at December 31, 2014 — $ — Granted 105,900 $ 30.85 Forfeited (12,450 ) $ 30.92 Non-vested restricted stock units at December 31, 2015 93,450 $ 30.84

Retirement Plans (Notes)

Retirement Plans (Notes)	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Retirement Plans [Text Block]	Retirement Plans As of December 31, 2015 , we maintained a qualified defined contribution plan. Our qualified defined contribution plan covers substantially all employees and complies with Section 401 of the Internal Revenue Code. Under this plan, we stipulated a basic matching contribution that matches a portion of the participants' contribution based upon a defined schedule. Additionally, this plan contains a discretionary contribution component where the Company may contribute additional amounts based on a percentage of eligible employees' compensation. Contributions are invested by an independent investment company. The choice of investment alternatives is at the election of each participating employee. Our contributions to the plan were approximately $18.5 million , $18.6 million and $19.3 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. We maintained an Employee Stock Ownership Plan (ESOP) as of December 31, 2015 . On December 18, 1998, the Board of Directors approved the establishment of a qualified ESOP, effective January 1, 1999, for the benefit of substantially all of our U.S. domestic-based employees and some overseas employees. The ESOP is non-leveraged and is funded entirely through Company contributions based on a percentage of eligible employee compensation, as defined in the plan. Participants must be employees of the Company or eligible Company subsidiaries and must meet minimum service requirements to be eligible for annual contributions. The ESOP specifies a five -year vesting schedule over which participants become vested in the Class A common stock allocated to their participant account. The amount of our annual contribution to the ESOP is at the discretion of our Board of Directors. For the years ended December 31, 2015 , 2014 and 2013 , we recorded $0 , $0 and $0.9 million , respectively, as compensation expense related to ESOP contributions. There were 0 shares, 0 shares and 31,653 shares of Class A common stock contributed to the ESOP for the years ended December 31, 2015 , 2014 and 2013 , respectively. As required under ASC 718-40 , Compensation - Stock Compensation - Employee Stock Ownership Plans , compensation expense is recorded for shares committed to be released to employees based on the fair market value of those shares in the period in which they are committed to be released. For the years ended December 31, 2014 and 2013 , new shares were issued to satisfy this obligation. As of December 31, 2015 , we also maintained an Employee Supplemental Savings Plan (ESSP), a non-qualified deferred compensation plan, for certain key employees. Under this plan, eligible employees may defer up to 75% of qualified annual base compensation and 100% of bonus. In the ESSP, participant deferral accounts are credited with a rate of return based on investment elections as selected by the participant. The assets related to the ESSP are held in a rabbi trust owned by the Company for benefit of the participating employees. The trust investments are in the form of variable universal life insurance products, which are owned by the Company. These investments seek to replicate the return of the participant investment elections. Employee contributions to this plan were approximately $2.8 million , $3.0 million and $3.2 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. We maintained a nonqualified supplemental defined benefit pension plan for certain retired employees of an acquired company as of December 31, 2015 . These plans were informally and partially funded beginning in 1999 through a rabbi trust. Assets held in a rabbi trust are not eligible to be included in the calculation of plan status. At both December 31, 2015 and 2014 , 100% of the rabbi trust assets were invested in a money market account with a commercial bank. All covered employees retired prior to 1998. Our benefit obligation was $1.1 million and $1.3 million at December 31, 2015 and 2014 , respectively.

Income Taxes (Notes)

Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes The domestic and foreign components of income operations before income taxes and equity method investments were as follows (in thousands): Year Ended 2015 2014 2013 Domestic $ 85,665 $ 79,238 $ 6,768 Foreign (311 ) (137 ) (215 ) Income from operations before income taxes and equity method investments $ 85,354 $ 79,101 $ 6,553 The provision for income taxes was comprised of the following components (in thousands): Year Ended 2015 2014 2013 Current provision: Federal $ 2,714 $ 10,375 $ 18,702 State 1,247 2,499 4,011 Foreign 77 160 86 4,038 13,034 22,799 Deferred provision (benefit): Federal 27,817 17,739 (6,557 ) State 5,825 4,477 (1,858 ) 33,642 22,216 (8,415 ) Non-current provision (benefit) resulting from allocating tax benefits directly to additional paid in capital and changes in liabilities: Federal (2,568 ) (2,755 ) (2,009 ) State (746 ) (970 ) (522 ) Foreign — — (11 ) (3,314 ) (3,725 ) (2,542 ) Provision for income taxes $ 34,366 $ 31,525 $ 11,842 For the years ended December 31, 2015 , 2014 and 2013 , the non-current benefit for income taxes includes $3.0 million , $3.3 million and $2.4 million , respectively, arising from the cancellation of vested stock options allocated to equity and valuation differences between grant date and vesting dates on restricted stock allocated to equity and $0.3 million , $0.4 million and $0.1 million , respectively, related to liabilities for uncertain tax positions. The schedule of effective income tax rate reconciliation is as follows: Year Ended 2015 2014 2013 Statutory U.S. Federal tax rate 35.0 % 35.0 % 35.0 % Increase (decrease) in tax rate resulting from: State taxes—net of Federal benefit 4.8 % 5.0 % 18.6 % Excess executive compensation 0.5 % 1.3 % 16.7 % Section 199 deductions (0.4 )% (0.6 )% (6.5 )% Deferred compensation (ESSP) 0.2 % (0.7 )% (24.6 )% Goodwill impairment — % — % 200.1 % Tax basis deduction of investment — % — % (15.3 )% Provisions of American Taxpayer Relief Act of 2012 — % — % (10.3 )% Acquisition working capital settlement — % — % (5.0 )% Other, net 0.1 % — % (0.7 )% Effective tax rate 40.2 % 40.0 % 208.0 % The Company paid income taxes, net of refunds, of $6.4 million , $14.3 million and $14.9 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Deferred income taxes arise from temporary differences between the tax basis of assets and liabilities and their reported amounts in the financial statements. A summary of the tax effect of the significant components of deferred income taxes is as follows (in thousands): December 31, 2015 2014 Gross deferred tax liabilities: Goodwill and other assets $ 111,156 $ 86,242 Unbilled receivables 19,154 14,549 Property and equipment 4,554 3,931 Total 134,864 104,722 Gross deferred tax assets: Retirement and other liabilities (29,000 ) (31,851 ) Allowance for potential contract losses and other contract reserves (3,429 ) (3,911 ) Federal and state operating loss carryforwards (400 ) (441 ) Total (32,829 ) (36,203 ) Net deferred tax liabilities $ 102,035 $ 68,519 The tax benefits associated with nonqualified stock options and disqualifying dispositions of incentive stock options reduced the current taxes payable by $0.1 million for the year ended December 31, 2015 . These benefits were recorded as an increase to additional paid-in capital. At December 31, 2015 , we had state net operating losses of approximately $9.2 million that expire beginning 2017 through 2033 . A reconciliation of the beginning and ending balances of the total amounts of gross unrecognized tax benefits is as follows (in thousands): December 31, 2015 2014 2013 Gross unrecognized tax benefits at beginning of year $ 785 $ 1,207 $ 1,376 Lapse in statute of limitations (266 ) (575 ) (307 ) Increases in tax positions for prior years — 80 95 Decreases in tax positions for prior years — (13 ) (26 ) Increases in tax positions for current year — 86 69 Gross unrecognized tax benefits at end of year $ 519 $ 785 $ 1,207 The total liability for gross unrecognized tax benefits as of December 31, 2015 , 2014 and 2013 includes $0.4 million , $0.6 million and $0.9 million , respectively, of unrecognized net tax benefits which, if ultimately recognized, would reduce our annual effective tax rate in a future period. The Company is subject to income taxes in the U.S., various state and foreign jurisdictions. Tax statutes and regulations within each jurisdiction are subject to interpretation and require significant judgment to apply. The Company is no longer subject to U.S., state or non-U.S. income tax examinations by tax authorities for the years before 2011. The Company believes it is reasonably possible that $0.3 million of gross unrecognized tax benefits will be settled within the next year due to expirations of statute of limitations. The Company recognizes interest related to unrecognized tax benefits within interest expense and penalties related to unrecognized tax benefits in general and administrative expenses. At December 31, 2015 , 2014 and 2013 , interest and penalties on the net unrecognized tax benefits were $0.1 million , $0.2 million and $0.2 million , respectively.

Business Segment and Geographic

Business Segment and Geographic Area Information (Notes)	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Business Segment And Geographic Area Information [Text Block]	Business Segment and Geographic Area Information We have one reportable segment. We deliver a broad array of IT and technical services solutions under contracts with the U.S. government. Our U.S. government customers typically exercise independent contracting authority, and even offices or divisions within an agency or department may directly, or through a prime contractor, use our services as a separate customer so long as that customer has independent decision-making and contracting authority within its organization. The U.S. Army Tank-Automotive Armament Command contract accounted for 5.6% , 7.5% and 19.4% of our revenues for the years ended December 31, 2015 , 2014 and 2013 , respectively. Revenues from the U.S. government under prime contracts and subcontracts were approximately 98.9% , 98.9% and 99.0% of our total revenues for the years ended December 31, 2015 , 2014 and 2013 , respectively. We treat sales to U.S. government customers as sales within the United States regardless of where the services are performed. U.S. revenues were approximately 99.9% , 99.7% and 99.8% of our total revenues for the years ended December 31, 2015 , 2014 and 2013 , respectively. International revenues were approximately 0.1% , 0.3% and 0.2% of our total revenues for the years ended December 31, 2015 , 2014 and 2013 , respectively. Furthermore, substantially all assets from continuing operations were held in the United States for the years ended December 31, 2015 , 2014 and 2013 .

Divestiture of ManTech Cyber So

Divestiture of ManTech Cyber Solutions and Investment in CounterTack Inc. (Notes)	12 Months Ended
	Dec. 31, 2015
Divestiture [Abstract]
Divestiture of ManTech Cyber Solutions International and Investment in CounterTack Inc. [Text Block]	Divestiture of ManTech Cyber Solutions International and Investment in CounterTack Inc. On July 13, 2015, we divested ManTech Cyber Solutions International (MCSI), which was engaged in the business of providing commercial cyber products. We received consideration of preferred stock in CounterTack Inc. that has a fair value of $6.7 million . The fair value is based on the quoted price for the identical item held by another party (Level 2). We recorded a gain on the sale of $1.7 million , which is included in the other income (expense), net line item on the consolidated statement of income for the year ended December 31, 2015. We divested assets of $5.5 million and liabilities of $1.7 million . We recorded transaction costs associated with the divestiture of $1.2 million . The divestiture did not qualify to be presented as discontinued operations as it did not represent a strategic shift that would have a major effect on our operations and financial results. On July 13, 2015, we purchased additional preferred stock in CounterTack Inc. for $3.8 million . This additional cash investment, along with the consideration received for the sale of MCSI, was accounted for under the cost method of accounting for investments.

Quarterly Financial Information

Quarterly Financial Information (Unaudited) (Notes)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information [Text Block]	Quarterly Financial Information (Unaudited) The quarterly financial data reflects, in the opinion of the Company, all normal and recurring adjustments to present fairly the results of operations for such periods. Results of any one or more quarters are not necessarily indicative of annual results or continuing trends. The following tables set forth selected unaudited quarterly financial data: 2015 March 31, June 30, September 30, December 31, (in thousands, except per share data) Revenues $ 370,330 $ 384,378 $ 393,008 $ 402,401 Operating income $ 19,846 $ 21,112 $ 21,120 $ 22,808 Income from operations before income taxes and equity method investments $ 19,497 $ 20,879 $ 22,353 $ 22,625 Net income $ 11,758 $ 12,450 $ 13,028 $ 13,891 Class A common stock: Basic weighted average common shares outstanding 24,206 24,325 24,341 24,393 Basic earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Diluted weighted average common shares outstanding 24,359 24,426 24,406 24,513 Diluted earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Class B common stock: Basic weighted average common shares outstanding 13,193 13,193 13,193 13,193 Basic earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Diluted weighted average common shares outstanding 13,193 13,193 13,193 13,193 Diluted earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 2014 March 31, June 30, September 30, December 31, (in thousands, except per share data) Revenues $ 452,033 $ 463,381 $ 447,200 $ 411,367 Operating income $ 20,042 $ 24,070 $ 26,732 $ 23,972 Income from operations before income taxes and equity method investments $ 16,059 $ 12,929 $ 26,492 $ 23,621 Net income $ 9,634 $ 7,708 $ 15,487 $ 14,465 Class A common stock: Basic weighted average common shares outstanding 23,988 24,023 24,061 24,115 Basic earnings per share $ 0.26 $ 0.21 $ 0.42 $ 0.39 Diluted weighted average common shares outstanding 24,057 24,092 24,126 24,191 Diluted earnings per share $ 0.26 $ 0.21 $ 0.41 $ 0.39 Class B common stock: Basic weighted average common shares outstanding 13,193 13,193 13,193 13,193 Basic earnings per share $ 0.26 $ 0.21 $ 0.42 $ 0.39 Diluted weighted average common shares outstanding 13,193 13,193 13,193 13,193 Diluted earnings per share $ 0.26 $ 0.21 $ 0.41 $ 0.39

Schedule II

Schedule II	12 Months Ended
	Dec. 31, 2015
Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	SCHEDULE II Valuation and Qualifying Accounts Activities in our allowance accounts for the years ended December 31, 2015 , 2014 and 2013 were as follows (in thousands): Doubtful Accounts Balance at Beginning of Period Charged to Costs and Expenses Deductions Other* Balance at End of Period 2013 $ 9,449 — — 587 $ 10,036 2014 $ 10,036 — (165 ) (41 ) $ 9,830 2015 $ 9,830 — (552 ) (805 ) $ 8,473 * Other represents doubtful account reserves released or recorded as part of net revenues for estimated customer disallowances. Deferred Tax Asset Valuation Balance at Beginning of Period Charged to Costs and Expenses Deductions Other Balance at End of Period 2013 $ — 191 — — $ 191 2014 $ 191 — (127 ) — $ 64 2015 $ 64 — — (64 ) $ —

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Principles of Consolidation [Policy Text Block]	Principles of Consolidation -Our consolidated financial statements include the accounts of ManTech International Corporation, subsidiaries we control and variable interest entities that are required to be consolidated. All intercompany accounts and transactions have been eliminated. Investments in entities where we have significant influence, but not control, are accounted for using the equity method.
Use of Accounting Estimates [Policy Text Block]	Use of Accounting Estimates -We prepare our consolidated financial statements in conformity with generally accepted accounting principles in the United States of America (GAAP), which require management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. These estimates involve judgments with respect to, among other things, various future economic factors that are difficult to predict and are beyond the control of the Company. Therefore, actual amounts could differ from these estimates.
Revenue Recognition [Policy Text Block]	Revenue Recognition -We derive the majority of our revenues from cost-plus-fixed-fee, cost-plus-award-fee, firm-fixed-price or time-and-materials contracts. Revenues for cost-reimbursable contracts are recorded as reimbursable costs are incurred, including an estimated share of the applicable contractual fees earned. For performance-based fees under cost-reimbursable contracts, we recognize the relevant portion of the expected fee to be awarded by the customer at the time such fee can be reasonably estimated, based on factors such as our prior award experience and communications with the customer regarding performance, or upon approval by the customer. For time-and-materials contracts, revenues are recognized to the extent of billable rates times hours delivered plus materials and other reimbursable costs incurred. For long-term fixed-price production contracts, revenues are recognized at a rate per unit as the units are delivered or by other methods to measure services provided. Revenues from other long-term fixed-price contracts are recognized ratably over the contract period or by other appropriate methods to measure services provided. Contract costs are expensed as incurred except for certain limited long-term contracts noted below. For long-term contracts, specifically described in the scope section of Accounting Standards Codification (ASC) 605-35 , Revenue Recognition - Construction-Type and Production-Type Contracts , we apply the percentage of completion method. Under the percentage of completion method, income is recognized at a consistent profit margin over the period of performance based on estimated profit margins at completion of the contract. This method of accounting requires estimating the total revenues and total contract costs at completion of the contract. During the performance of long-term contracts, these estimates are periodically reviewed and revisions are made as required using the cumulative catch-up method of accounting. The impact on revenues and contract profit as a result of these revisions is included in the periods in which the revisions are made. This method can result in the deferral of costs or the deferral of profit on these contracts. Because we assume the risk of performing a fixed-price contract at a set price, the failure to accurately estimate ultimate costs or to control costs during performance of the work could result, and in some instances has resulted, in reduced profits or losses for such contracts. Estimated losses on contracts at completion are recognized when identified. In certain circumstances, revenues are recognized when contract amendments have not been finalized.
Cost of Services [Policy Text Block]	Cost of Services -Cost of services consists primarily of compensation expenses for program personnel, the fringe benefits associated with this compensation and other direct expenses incurred to complete programs, including cost of materials and subcontract efforts.
General and Administrative Expenses [Policy Text Block]	General and Administrative Expenses- General and administrative expenses include the salaries and wages, plus associated fringe benefits of our employees not performing work directly for customers, and associated facilities costs. Among the functions covered by these costs are corporate business development, bid and proposal, contracts administration, finance and accounting, legal, corporate governance and executive and senior management. In addition, we included stock-based compensation, as well as depreciation and amortization expenses related to the general and administrative function. We classify indirect costs incurred as cost of services and general and administrative expenses in the same manner as such costs are defined in our disclosure statements under U.S. Government Cost Accounting Standards. Effective January 1, 2014, we updated our disclosure statements with the DCMA, resulting in certain costs being classified differently either as cost of services or as general and administrative expenses on a prospective basis. This change has caused a net increase in the reported cost of services and a net decrease in reported general and administrative expenses in 2015 and 2014 as compared to 2013; however, total operating costs were not affected by this change.
Cash and Cash Equivalents [Policy Text Block]	Cash and Cash Equivalents -For the purpose of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks and short-term investments with maturity dates of three months or less at the date of purchase. Due to the short maturity of cash equivalents, the carrying value on our consolidated balance sheets approximates fair value.
Property and Equipment [Policy Text Block]	Property and Equipment -Property and equipment are recorded at original cost to the Company. Upon sale or retirement, the costs and related accumulated depreciation or amortization are eliminated from the respective accounts and any resulting gain or loss is included in income. Maintenance and repairs are charged to expense as incurred.
Depreciation and Amortization Method [Policy Text Block]	Depreciation and Amortization Method -Furniture and office equipment are depreciated using the straight-line method with estimated useful lives ranging from one to seven years . Leasehold improvements are amortized using the straight-line method over the term of the lease.
Goodwill [Policy Text Block]	Goodwill -The purchase price of an acquired business is allocated to the tangible assets, financial assets and separately recognized intangible assets acquired less liabilities assumed based upon their respective fair values, with the excess recorded as goodwill. We review goodwill at least annually for impairment, or whenever events or circumstances indicate that the carrying value of long-lived assets may not be fully recoverable.
Other Intangible Assets [Policy Text Block]	Other Intangible Assets -Contract rights and other intangible assets are amortized primarily using the pattern of benefits method over periods ranging from one to twenty-five years . We account for the cost of computer software developed or obtained for internal use in accordance with ASC 350-985 , Intangibles - Goodwill and Other - Software . These capitalized software costs are included in other intangible assets, net. We account for software development costs related to software products for sale, lease or otherwise marketed in accordance with ASC 985-20 , Software - Costs of Software to Be Sold, Leased, or Marketed . For projects fully funded by us, development costs are capitalized from the point of demonstrated technological feasibility until the point in time that the product is available for general release to customers. Once the product is available for general release, capitalized costs are amortized based on units sold or on a straight-line basis over a five -year period or other such shorter period as may be required.
Impairment of Long-Lived Assets [Policy Text Block]	Impairment of Long-Lived Assets- Whenever events or changes in circumstances indicate that the carrying amount of long-lived assets may not be fully recoverable, we evaluate the probability that future undiscounted net cash flows will be less than the carrying amount of the assets. If any impairment were indicated as a result of this review, we would recognize a loss based on the amount by which the carrying amount exceeds the estimated fair value.
Employee Supplemental Savings Plan Assets [Policy Text Block]	Employee Supplemental Savings Plan Assets -We maintain several non-qualified defined contribution supplemental retirement plans for certain key employees that are accounted for in accordance with ASC 710-10-05 , Compensation - General - Deferred Compensation - Rabbi Trust , as the underlying assets are held in rabbi trusts with investments directed by the respective employee. A rabbi trust is a grantor trust generally set up to fund compensation for a select group of management and the assets of this trust are available to satisfy the claims of general creditors in the event of bankruptcy of the Company. The assets held by the rabbi trusts are recorded at cash surrender value in our consolidated financial statements as Employee Supplemental Savings Plan (ESSP) assets with a related liability to employees recorded as a deferred compensation liability in accrued retirement. We reclassified ESSP assets from the other line item in cash flow from operating activities of the consolidated statement of cash flows for the years ended December 31, 2014 and 2013 to conform with current period presentation.
Billings In Excess of Revenue Earned [Policy Text Block]	Billings In Excess of Revenue Earned -We receive advances and milestone payments from customers that exceed the revenues earned to date. We classify such items as current liabilities.
Stock-based Compensation [Policy Text Block]	Stock-based Compensation -We account for stock-based compensation in accordance with ASC 718 , Compensation - Stock Compensation , which requires the use of a valuation model to calculate the fair value of stock-based awards. We have elected to use the Black-Scholes-Merton pricing model to determine fair value on the dates of grant. The fair value is included in operating expenses or capitalized, as appropriate, straight-line over the period in which service is provided in exchange for the award. The grant date fair value of the restricted stock is equal to the closing market price of our common stock on the date of grant. The compensation expense for restricted stock is recognized over the service period and is based on the grant date fair value of the stock and the number of shares expected to vest. The grant date fair value of the restricted stock unit (RSU) is equal to the closing market price of our common stock on the grant date less the present value of dividends expected to be awarded during the service period. We recognize the grant date fair value of RSUs of shares we expect to issue as compensation expense ratably over the requisite service period.
Income Taxes [Policy Text Block]	Income Taxes -We account for income taxes in accordance with ASC 740 , Income Taxes . Under this method, deferred income taxes are determined based on the estimated future tax effects of differences between the financial statement and tax bases of assets and liabilities given the provisions of enacted tax laws. Deferred income tax provisions and benefits are based on changes to the assets or liabilities from year-to-year. In providing for deferred taxes, we consider tax regulations of the jurisdictions in which we operate, estimates of future taxable income and available tax planning strategies. If tax regulations, operating results or the ability to implement tax-planning strategies vary, adjustments to the carrying value of deferred tax assets and liabilities may be required. Valuation allowances are recorded related to deferred tax assets based on the “more likely than not” criteria. We recognize the financial statement benefit of a tax position only after determining that the relevant tax authority would “more likely than not” sustain the position following an audit. For tax positions meeting the “more likely than not” threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority. Due to a change in accounting principle resulting from Accounting Standards Update (ASU) 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, the deferred tax liabilities and assets are classified as noncurrent in our consolidated balance sheet as of December 31, 2015. The prior periods were not retrospectively adjusted. Therefore, the deferred income tax liabilities and assets are classified into current and noncurrent amounts in our consolidated balance sheet as of December 31, 2014.
Foreign-Currency Translation [Policy Text Block]	Foreign-Currency Translation -All assets and liabilities of foreign subsidiaries are translated into U.S. dollars at fiscal year-end exchange rates. Income and expense items are translated at average monthly exchange rates prevailing during the fiscal year. The resulting translation adjustments are recorded as a component of accumulated other comprehensive income (loss).
Comprehensive Income (Loss) [Policy Text Block]	Comprehensive Income (Loss) -Comprehensive income (loss) is presented in our consolidated statements of changes in stockholders' equity. Comprehensive income (loss) consists of net income (loss); translation adjustments, net of tax; and actuarial gain (loss) on defined benefit pension plan, net of tax.
Fair Value of Financial Instruments [Policy Text Block]	Fair Value of Financial Instruments -The carrying value of our cash and cash equivalents, accounts receivable, accounts payable and accrued expenses approximate their fair value because of the short-term nature of these amounts.
Variable Interest Entities [Policy Text Block]	Variable Interest Entities -We determine whether we have a controlling financial interest in a variable interest entity (VIE). The reporting entity with a variable interest or interest that provides the reporting entity with a controlling financial interest in a VIE will have both (a) the power to direct the activities of a VIE that most significantly impact the VIE's economic performance and (b) the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits from the VIE that could potentially be significant to the VIE. We have one entity that has been consolidated as a VIE. The purpose of the entity is to perform on certain U.S. Navy contracts. The maximum amount of loss we are exposed to as of December 31, 2015 was not material to our consolidated financial statements.
Investments [Policy Text Block]	Investments -Investments where we have the ability to exercise significant influence, but we do not control, are accounted for under the equity method of accounting and are included in other assets on our consolidated balance sheets. Significant influence typically exists if we have a 20% to 50% ownership interest in the investee. Under this method of accounting, our share of the net earnings or losses of the investee is included in equity in earnings or losses of unconsolidated subsidiaries on our consolidated statement of income and loss. Investments where we have less than 20% ownership interest in the investee and lack the ability to exercise significant influence are accounted for under the cost method. Under the cost method, we recognize our investment in the stock of an investee as an asset. The investment is measured initially at cost. We recognize as income dividends received that are distributed from net accumulated earnings. Dividends received in excess of earnings are considered a return of investment and are recorded as reductions of costs of the investment. Impairment is assessed at the individual investment level. An investment is impaired if the fair value of the investment is less than its costs. If it is determined that the impairment is other than temporary, then an impairment loss is recognized in earnings. The fair value of the investment would become the new cost basis of the investment and will not be adjusted for subsequent recoveries in fair value. We reclassified investments from the other assets line item on the consolidated balance sheet at December 31, 2014 to conform with the current period presentation.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2015
Knowledge Consulting Group [Member]
Business Combination Segment Allocation [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table represents the purchase price allocation for KCG (in thousands): Knowledge Consulting Group, Inc. Cash and cash equivalents $ 658 Receivables 6,532 Prepaid expenses and other 460 Goodwill 47,487 Other intangible assets 13,219 Property and equipment 1,419 Investments 15 Other assets 31 Accounts payable and accrued expenses (1,269 ) Accrued salaries and related expenses (336 ) Billings in excess of revenue earned (2 ) Net assets acquired and liabilities assumed $ 68,214
Welkin Associates, Ltd. [Member]
Business Combination Segment Allocation [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table represents the purchase price allocation for Welkin (in thousands): Welkin Associates, Ltd. Receivables $ 3,901 Prepaid expenses and other 141 Goodwill 24,436 Other intangible assets 6,350 Property and equipment 100 Accounts payable and accrued expenses (436 ) Accrued salaries and related expenses (492 ) Net assets acquired and liabilities assumed $ 34,000
7Delta Inc. [Member]
Business Combination Segment Allocation [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table represents the purchase price allocation for 7Delta (in thousands): 7Delta Inc. Cash and cash equivalents $ 1,408 Receivables 9,664 Prepaid expenses and other 175 Goodwill 69,967 Other intangible assets 7,762 Property and equipment 597 Other assets 39 Accounts payable and accrued expenses (6,617 ) Accrued salaries and related expenses (1,399 ) Billings in excess of revenue earned (229 ) Net assets acquired and liabilities assumed $ 81,367
Allied Technology Group Inc [Member]
Business Combination Segment Allocation [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following table represents the purchase price allocation for ATG (in thousands): Allied Technology Group, Inc. Cash and cash equivalents $ 712 Receivables 11,670 Prepaid expenses and other 1,432 Contractual inventory 1 Goodwill 28,806 Other intangible assets 7,071 Property and equipment 899 Other assets 111 Accounts payable and accrued expenses (3,399 ) Accrued salaries and related expenses (2,155 ) Billings in excess of revenue earned (148 ) Net assets acquired and liabilities assumed $ 45,000

Earnings (Loss) per Share (Tabl

Earnings (Loss) per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Schedule of Earnings (Loss) Per Share, Basic and Diluted [Table Text Block]	The net income (loss) available to common stockholders and weighted average number of common shares outstanding used to compute basic and diluted earnings (loss) per share for each class of common stock are as follows (in thousands, except per share amounts): Year Ended 2015 2014 2013 Distributed earnings $ 31,543 $ 31,313 $ 31,200 Undistributed earnings (loss) 19,584 15,981 (37,349 ) Net income (loss) $ 51,127 $ 47,294 $ (6,149 ) Class A common stock: Basic net income (loss) available to common stockholders $ 33,145 $ 30,539 $ (3,963 ) Basic weighted average common shares outstanding 24,317 24,047 23,913 Basic earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Diluted net income (loss) available to common stockholders $ 33,197 $ 30,571 $ (3,963 ) Effect of potential exercise of stock options 109 70 — Diluted weighted average common shares outstanding 24,426 24,117 23,913 Diluted earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Class B common stock: Basic net income (loss) available to common stockholders $ 17,982 $ 16,755 $ (2,186 ) Basic weighted average common shares outstanding 13,193 13,193 13,193 Basic earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 ) Diluted net income (loss) available to common stockholders $ 17,930 $ 16,723 $ (2,186 ) Effect of potential exercise of stock options — — — Diluted weighted average common shares outstanding 13,193 13,193 13,193 Diluted earnings (loss) per share $ 1.36 $ 1.27 $ (0.17 )

Receivables (Tables)

Receivables (Tables)	12 Months Ended
	Dec. 31, 2015
Receivables [Abstract]
Schedule of Contract Receivables [Table Text Block]	The components of contract receivables are as follows (in thousands): December 31, 2015 2014 Billed receivables $ 233,735 $ 319,065 Unbilled receivables: Amounts billable 47,900 50,393 Revenues recorded in excess of funding 19,213 13,082 Retainage 11,878 4,446 Allowance for doubtful accounts (8,473 ) (9,830 ) Receivables-net $ 304,253 $ 377,156

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment [Table Text Block]	Major classes of property and equipment are summarized as follows (in thousands): December 31, 2015 2014 Furniture and equipment $ 44,718 $ 43,659 Leasehold improvements 35,733 35,601 Property and equipment-gross 80,451 79,260 Accumulated depreciation and amortization (58,012 ) (53,517 ) Property and equipment-net $ 22,439 $ 25,743

Goodwill and Other Intangible29

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill [Table Text Block]	The changes in the carrying amounts of goodwill during fiscal years 2015 and 2014 were as follows (in thousands): Goodwill Balance Goodwill at December 31, 2013 $ 752,867 Acquisitions 98,773 Goodwill at December 31, 2014 851,640 Acquisitions 71,922 Divestiture (3,971 ) Goodwill at December 31, 2015 $ 919,591
Schedule of Other Intangible Assets [Table Text Block]	Other intangible assets consisted of the following (in thousands): December 31, 2015 December 31, 2014 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Other intangible assets: Contract and program intangible assets $ 281,682 $ 140,163 $ 141,519 $ 266,272 $ 126,619 $ 139,653 Capitalized software cost for internal use 36,170 23,522 12,648 35,036 19,500 15,536 Other 58 49 9 115 54 61 Total other intangible assets-net $ 317,910 $ 163,734 $ 154,176 $ 301,423 $ 146,173 $ 155,250
Schedule of Other Intangible Assets, Future Amortization Expense [Table Text Block]	We estimate that we will have the following amortization expense for the future periods indicated below (in thousands): Year ending: December 31, 2016 $ 21,484 December 31, 2017 $ 20,018 December 31, 2018 $ 18,314 December 31, 2019 $ 15,836 December 31, 2020 $ 12,614

Commitments and Contingencies30

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	At December 31, 2015 , aggregate future minimum rental commitments under these leases are as follows (in thousands): Total Year ending: December 31, 2016 $ 30,202 December 31, 2017 25,643 December 31, 2018 22,740 December 31, 2019 21,560 December 31, 2020 15,501 Thereafter 40,255 Total $ 155,901

Stockholders Equity and Stock31

Stockholders Equity and Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	The following table summarizes weighted-average assumptions used in our calculations of fair value for the years ended December 31, 2015 , 2014 and 2013 : Year Ended 2015 2014 2013 Volatility 26.16 % 28.96 % 31.92 % Expected life of options 3 years 3 years 3 years Risk-free interest rate 1.15 % 0.96 % 0.56 % Dividend yield 3.00 % 3.00 % 3.00 %
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]	The following table summarizes stock option activity for the years ended December 31, 2015 , 2014 and 2013 : Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value Stock options at December 31, 2012 3,421,196 $ 38.61 $ 626 Granted 957,525 $ 27.42 Exercised (79,567 ) $ 22.75 $ 400 Cancelled and expired (899,034 ) $ 39.84 Stock options at December 31, 2013 3,400,120 $ 35.51 $ 4,488 Granted 946,576 $ 29.12 Exercised (158,371 ) $ 24.78 $ 754 Cancelled and expired (797,293 ) $ 41.75 Stock options at December 31, 2014 3,391,032 $ 32.76 $ 4,722 Granted 237,853 $ 30.87 Exercised (284,320 ) $ 27.51 $ 1,348 Cancelled and expired (849,255 ) $ 39.56 Stock options at December 31, 2015 2,495,310 $ 30.86 $ 3,583
Schedule of Non-Vested Share Activity [Table Text Block]	The following table summarizes non-vested stock options for the year ended December 31, 2015 : Number of Shares Weighted Average Fair Value Non-vested stock options at December 31, 2014 1,673,528 $ 4.83 Granted 237,853 $ 4.59 Vested (726,750 ) $ 4.89 Cancelled (193,341 ) $ 4.79 Non-vested stock options at December 31, 2015 991,290 $ 4.74
Stock Options Exercisable And Expected To Vest [Table Text Block]	The following table includes information concerning stock options exercisable and stock options expected to vest at December 31, 2015 : Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Aggregate Intrinsic Value Stock options exercisable 1,504,020 2 years $ 32.01 $ 2,236 Stock options expected to vest 894,966 4 years $ 29.08 $ 1,242 Stock options exercisable and expected to vest 2,398,986
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Compensation, Restricted Stock Activity [Table Text Block]	The following table summarizes the restricted stock activity during the years ended December 31, 2014 and 2015 : Number of Shares Weighted Average Fair Value Non-vested restricted stock at December 31, 2013 21,000 $ 27.65 Granted 21,000 $ 30.61 Vested (21,000 ) $ 27.65 Non-vested restricted stock at December 31, 2014 21,000 $ 30.61 Granted 21,000 $ 28.98 Vested (21,000 ) $ 30.61 Non-vested restricted stock at December 31, 2015 21,000 $ 28.98
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Compensation, Restricted Stock Activity [Table Text Block]	The following table summarizes the nonvested restricted stock unit activity during the year ended December 31, 2015. There was no restricted stock unit activity during the year ended December 31, 2014. Number of Units Weighted Average Fair Value Non-vested restricted stock units at December 31, 2014 — $ — Granted 105,900 $ 30.85 Forfeited (12,450 ) $ 30.92 Non-vested restricted stock units at December 31, 2015 93,450 $ 30.84

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]	The domestic and foreign components of income operations before income taxes and equity method investments were as follows (in thousands): Year Ended 2015 2014 2013 Domestic $ 85,665 $ 79,238 $ 6,768 Foreign (311 ) (137 ) (215 ) Income from operations before income taxes and equity method investments $ 85,354 $ 79,101 $ 6,553
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	The provision for income taxes was comprised of the following components (in thousands): Year Ended 2015 2014 2013 Current provision: Federal $ 2,714 $ 10,375 $ 18,702 State 1,247 2,499 4,011 Foreign 77 160 86 4,038 13,034 22,799 Deferred provision (benefit): Federal 27,817 17,739 (6,557 ) State 5,825 4,477 (1,858 ) 33,642 22,216 (8,415 ) Non-current provision (benefit) resulting from allocating tax benefits directly to additional paid in capital and changes in liabilities: Federal (2,568 ) (2,755 ) (2,009 ) State (746 ) (970 ) (522 ) Foreign — — (11 ) (3,314 ) (3,725 ) (2,542 ) Provision for income taxes $ 34,366 $ 31,525 $ 11,842
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The schedule of effective income tax rate reconciliation is as follows: Year Ended 2015 2014 2013 Statutory U.S. Federal tax rate 35.0 % 35.0 % 35.0 % Increase (decrease) in tax rate resulting from: State taxes—net of Federal benefit 4.8 % 5.0 % 18.6 % Excess executive compensation 0.5 % 1.3 % 16.7 % Section 199 deductions (0.4 )% (0.6 )% (6.5 )% Deferred compensation (ESSP) 0.2 % (0.7 )% (24.6 )% Goodwill impairment — % — % 200.1 % Tax basis deduction of investment — % — % (15.3 )% Provisions of American Taxpayer Relief Act of 2012 — % — % (10.3 )% Acquisition working capital settlement — % — % (5.0 )% Other, net 0.1 % — % (0.7 )% Effective tax rate 40.2 % 40.0 % 208.0 %
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	A summary of the tax effect of the significant components of deferred income taxes is as follows (in thousands): December 31, 2015 2014 Gross deferred tax liabilities: Goodwill and other assets $ 111,156 $ 86,242 Unbilled receivables 19,154 14,549 Property and equipment 4,554 3,931 Total 134,864 104,722 Gross deferred tax assets: Retirement and other liabilities (29,000 ) (31,851 ) Allowance for potential contract losses and other contract reserves (3,429 ) (3,911 ) Federal and state operating loss carryforwards (400 ) (441 ) Total (32,829 ) (36,203 ) Net deferred tax liabilities $ 102,035 $ 68,519
Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]	A reconciliation of the beginning and ending balances of the total amounts of gross unrecognized tax benefits is as follows (in thousands): December 31, 2015 2014 2013 Gross unrecognized tax benefits at beginning of year $ 785 $ 1,207 $ 1,376 Lapse in statute of limitations (266 ) (575 ) (307 ) Increases in tax positions for prior years — 80 95 Decreases in tax positions for prior years — (13 ) (26 ) Increases in tax positions for current year — 86 69 Gross unrecognized tax benefits at end of year $ 519 $ 785 $ 1,207

Quarterly Financial Informati33

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information [Table Text Block]	The following tables set forth selected unaudited quarterly financial data: 2015 March 31, June 30, September 30, December 31, (in thousands, except per share data) Revenues $ 370,330 $ 384,378 $ 393,008 $ 402,401 Operating income $ 19,846 $ 21,112 $ 21,120 $ 22,808 Income from operations before income taxes and equity method investments $ 19,497 $ 20,879 $ 22,353 $ 22,625 Net income $ 11,758 $ 12,450 $ 13,028 $ 13,891 Class A common stock: Basic weighted average common shares outstanding 24,206 24,325 24,341 24,393 Basic earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Diluted weighted average common shares outstanding 24,359 24,426 24,406 24,513 Diluted earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Class B common stock: Basic weighted average common shares outstanding 13,193 13,193 13,193 13,193 Basic earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 Diluted weighted average common shares outstanding 13,193 13,193 13,193 13,193 Diluted earnings per share $ 0.31 $ 0.33 $ 0.35 $ 0.37 2014 March 31, June 30, September 30, December 31, (in thousands, except per share data) Revenues $ 452,033 $ 463,381 $ 447,200 $ 411,367 Operating income $ 20,042 $ 24,070 $ 26,732 $ 23,972 Income from operations before income taxes and equity method investments $ 16,059 $ 12,929 $ 26,492 $ 23,621 Net income $ 9,634 $ 7,708 $ 15,487 $ 14,465 Class A common stock: Basic weighted average common shares outstanding 23,988 24,023 24,061 24,115 Basic earnings per share $ 0.26 $ 0.21 $ 0.42 $ 0.39 Diluted weighted average common shares outstanding 24,057 24,092 24,126 24,191 Diluted earnings per share $ 0.26 $ 0.21 $ 0.41 $ 0.39 Class B common stock: Basic weighted average common shares outstanding 13,193 13,193 13,193 13,193 Basic earnings per share $ 0.26 $ 0.21 $ 0.42 $ 0.39 Diluted weighted average common shares outstanding 13,193 13,193 13,193 13,193 Diluted earnings per share $ 0.26 $ 0.21 $ 0.41 $ 0.39

Description of the Business (Na

Description of the Business (Narrative) (Details)	12 Months Ended
	Dec. 31, 2015contractsfederalagenices
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of Federal Agencies | federalagenices	50
Number of Contracts | contracts	1,000

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Narrative) (Details)	12 Months Ended
	Dec. 31, 2015Entities
Significant Accounting Policies [Line Items]
More Likely Than Not Threshold	50.00%
Number of Consolidated Variable Interest Entities	1
Minimum [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	1 year
Equity Method Investment, Ownership Percentage	20.00%
Maximum [Member]
Significant Accounting Policies [Line Items]
Maturity Threshold For Including In Cash And Cash Equivalent	3 months
Property, Plant and Equipment, Useful Life	7 years
Equity Method Investment, Ownership Percentage	50.00%
Other Intangible Assets [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year
Other Intangible Assets [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	25 years
Capitalized Software Cost For Sale [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Less than [Member]
Significant Accounting Policies [Line Items]
Cost Method Investment, Ownership Percentage	20.00%

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Knowledge Consulting Group [Member]
Business Acquisition [Line Items]
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed	$ 300
Business Combination, Consideration Transferred	68,200
Other intangible assets	$ 13,219
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	14 years
Knowledge Consulting Group [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 12,400
Finite-Lived Intangible Asset, Useful Life	15 years
Knowledge Consulting Group [Member] | Backlog [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 800
Finite-Lived Intangible Asset, Useful Life	1 year
Welkin Associates, Ltd. [Member]
Business Acquisition [Line Items]
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed	$ 700
Business Combination, Consideration Transferred	34,000
Other intangible assets	$ 6,350
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	14 years
Welkin Associates, Ltd. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 6,000
Finite-Lived Intangible Asset, Useful Life	15 years
Welkin Associates, Ltd. [Member] | Backlog [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 400
Finite-Lived Intangible Asset, Useful Life	1 year
7Delta Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed		$ 500
Business Combination, Consideration Transferred		81,400
Other intangible assets	$ 7,762
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years
7Delta Inc. [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 4,800
Finite-Lived Intangible Asset, Useful Life	10 years
7Delta Inc. [Member] | Backlog [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 2,900
Finite-Lived Intangible Asset, Useful Life	2 years
Allied Technology Group Inc [Member]
Business Acquisition [Line Items]
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed		400
Business Combination, Consideration Transferred		$ 45,000
Other intangible assets	$ 7,071
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	18 years
Allied Technology Group Inc [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 6,400
Finite-Lived Intangible Asset, Useful Life	20 years
Allied Technology Group Inc [Member] | Backlog [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 600
Finite-Lived Intangible Asset, Useful Life	1 year
ALTA Systems, Inc [Member]
Business Acquisition [Line Items]
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed			$ 100
Business Combination, Consideration Transferred			$ 10,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	$ 11,100
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	900
Other intangible assets	700
Business Acquisition, Goodwill, Expected Tax Deductible Amount	$ 9,100
Expected Goodwill Tax Amortization Period	15 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	17 years
ALTA Systems, Inc [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 600
Finite-Lived Intangible Asset, Useful Life	20 years
ALTA Systems, Inc [Member] | Backlog [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$ 100
Finite-Lived Intangible Asset, Useful Life	1 year

Acquisitions (Schedule of Recog

Acquisitions (Schedule of Recognized Identified Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 919,591	$ 851,640	$ 752,867
Knowledge Consulting Group [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	658
Receivables	6,532
Prepaid expenses and other	460
Goodwill	47,487
Other intangible assets	13,219
Property and equipment	1,419
Investments	15
Other assets	31
Accounts payable and accrued expenses	(1,269)
Accrued salaries and related expenses	(336)
Billings in excess of revenue earned	(2)
Net assets acquired and liabilities assumed	68,214
Welkin Associates, Ltd. [Member]
Business Acquisition [Line Items]
Receivables	3,901
Prepaid expenses and other	141
Goodwill	24,436
Other intangible assets	6,350
Property and equipment	100
Accounts payable and accrued expenses	(436)
Accrued salaries and related expenses	(492)
Net assets acquired and liabilities assumed	34,000
7Delta Inc. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	1,408
Receivables	9,664
Prepaid expenses and other	175
Goodwill	69,967
Other intangible assets	7,762
Property and equipment	597
Other assets	39
Accounts payable and accrued expenses	(6,617)
Accrued salaries and related expenses	(1,399)
Billings in excess of revenue earned	(229)
Net assets acquired and liabilities assumed	81,367
Allied Technology Group Inc [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	712
Receivables	11,670
Prepaid expenses and other	1,432
Contractual inventory	1
Goodwill	28,806
Other intangible assets	7,071
Property and equipment	899
Other assets	111
Accounts payable and accrued expenses	(3,399)
Accrued salaries and related expenses	(2,155)
Billings in excess of revenue earned	(148)
Net assets acquired and liabilities assumed	$ 45,000

Earnings (Loss) per Share (Narr

Earnings (Loss) per Share (Narrative) (Details) - $ / shares	3 Months Ended												12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Dividend Declared And Paid	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21	$ 0.21
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount													1,800,000	2,700,000	3,200,000
Options exercised, Number of Shares													284,320	158,371	79,567

(Schedule of Earnings (Loss) Pe

(Schedule of Earnings (Loss) Per Share, Basic and Diluted) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Components of Earnings (Loss) Per Share, Basic and Diluted [Line Items]
Distributed earnings									$ 31,543	$ 31,313	$ 31,200
Undistributed earnings									19,584	15,981
Undistributed (loss)											(37,349)
Net income (loss)	$ 13,891	$ 13,028	$ 12,450	$ 11,758	$ 14,465	$ 15,487	$ 7,708	$ 9,634	51,127	47,294	(6,149)
Class A Common Stock [Member]
Components of Earnings (Loss) Per Share, Basic and Diluted [Line Items]
Basic net income (loss) available to common stockholders									$ 33,145	$ 30,539	$ (3,963)
Basic weighted average common shares outstanding	24,393,000	24,341,000	24,325,000	24,206,000	24,115,000	24,061,000	24,023,000	23,988,000	24,317,000	24,047,000	23,913,000
Basic earnings (loss) per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.42	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Diluted net income (loss) available to common stockholders									$ 33,197	$ 30,571	$ (3,963)
Effect of potential exercise of stock options									109,000	70,000	0
Diluted weighted average common shares outstanding	24,513,000	24,406,000	24,426,000	24,359,000	24,191,000	24,126,000	24,092,000	24,057,000	24,426,000	24,117,000	23,913,000
Diluted earnings (loss) per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.41	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Class B Common Stock [Member]
Components of Earnings (Loss) Per Share, Basic and Diluted [Line Items]
Basic net income (loss) available to common stockholders									$ 17,982	$ 16,755	$ (2,186)
Basic weighted average common shares outstanding	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000
Basic earnings (loss) per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.42	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Diluted net income (loss) available to common stockholders									$ 17,930	$ 16,723	$ (2,186)
Effect of potential exercise of stock options									0	0	0
Diluted weighted average common shares outstanding	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000	13,193,000
Diluted earnings (loss) per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.41	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)

Receivables (Schedule of Contra

Receivables (Schedule of Contract Receivables) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Billed receivables	$ 233,735	$ 319,065
Unbilled receivables:
Amounts billable	47,900	50,393
Revenues recorded in excess of funding	19,213	13,082
Retainage	11,878	4,446
Allowance for doubtful accounts	(8,473)	(9,830)
Receivables-net	$ 304,253	$ 377,156

Receivables (Narrative) (Detail

Receivables (Narrative) (Details) $ in Millions	Dec. 31, 2015USD ($)
Receivables [Abstract]
Accounts Receivable Not Expected to be Substantially Collected within One Year	$ 0.6
Percentage of Accounts Receivable Not Expected to be Collected Within One Year related to Receivables from Direct Sales to U.S. Government	88.90%

Property and Equipment (Propert

Property and Equipment (Property and Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment-gross	$ 80,451	$ 79,260
Accumulated depreciation and amortization	(58,012)	(53,517)
Property and equipment-net	22,439	25,743
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment-gross	44,718	43,659
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment-gross	$ 35,733	$ 35,601

Property and Equipment (Narrati

Property and Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Depreciation and Amortization Expense	$ 8.5	$ 9	$ 8.7

Goodwill and Other Intangible44

Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of Intangible Assets	$ 21.2	$ 20.4	$ 20.4

Goodwill and Other Intangible45

Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Goodwill balance, period start	$ 851,640	$ 752,867
Acquisitions	71,922	98,773
Divestiture	(3,971)
Goodwill balance, period end	$ 919,591	$ 851,640

Goodwill and Other Intangible46

Goodwill and Other Intangible Assets (Schedule of Other Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 317,910	$ 301,423
Accumulated Amortization	163,734	146,173
Net Carrying Amount	154,176	155,250
Contract and program intangible assets
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	281,682	266,272
Accumulated Amortization	140,163	126,619
Net Carrying Amount	141,519	139,653
Capitalized software cost for internal use
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	36,170	35,036
Accumulated Amortization	23,522	19,500
Net Carrying Amount	12,648	15,536
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	58	115
Accumulated Amortization	49	54
Net Carrying Amount	$ 9	$ 61

Goodwill and Other Intangible47

Goodwill and Other Intangible Assets (Schedule of Other Intangible Assets, Future Amortization Expense) (Details) $ in Thousands	Dec. 31, 2015USD ($)
Year ending:
December 31, 2016	$ 21,484
December 31, 2017	20,018
December 31, 2018	18,314
December 31, 2019	15,836
December 31, 2020	$ 12,614

Debt (Revolving Credit Facility

Debt (Revolving Credit Facility) (Narrative) (Details) - USD ($)	Jun. 13, 2014	Dec. 31, 2015	Dec. 31, 2014
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Debt, Weighted Average Interest Rate		1.88%	0.76%
Bank of America Syndicate [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 500,000,000
Debt Issuance Cost	$ 3,400,000
Line of Credit, Current		0	$ 0
Line of Credit Facility, Average Outstanding Amount		11,100,000	9,100,000
Line of Credit Facility, Remaining Borrowing Capacity		480,800,000
Bank of America Syndicate [Member] | Letter of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		25,000,000
Letters of Credit Outstanding, Amount		19,200,000	$ 800,000
Bank of America Syndicate [Member] | Revolving Credit Facility, Swing Line Loan [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 30,000,000
Variable Spread [Member] | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.25%
Variable Spread [Member] | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.25%
Variable Spread [Member] | Bank of America's Base Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.25%
Variable Spread [Member] | Bank of America's Base Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.25%

Debt (Senior Unsecured Notes) (

Debt (Senior Unsecured Notes) (Narrative) (Details) - USD ($)	Apr. 15, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Apr. 13, 2010
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 0	$ 10,074,000	$ 0
7.25% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					7.25%
Debt Instrument, Face Amount					$ 200,000,000
Debt Instrument, Redemption Price, Percentage	103.625%
Debt Instrument, Redemption Price, Amount	$ 207,300,000

Commitments and Contingencies50

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]
Office space and equipment rent expense	$ 37.2	$ 42.9	$ 47.6
Deferred rent liabilties	11.1	11.1
Bank of America Syndicate [Member] | Letter of Credit [Member]
Line of Credit Facility [Line Items]
Letters of Credit Outstanding, Amount	19.2	$ 0.8
Performance Guarantee [Member] | Bank of America Syndicate [Member] | Letter of Credit [Member]
Line of Credit Facility [Line Items]
Letters of Credit Outstanding, Amount	$ 19

Commitments and Contingencies51

Commitments and Contingencies (Schedule of Future Minimum Rental Payments for Operating Leases) (Details) $ in Thousands	Dec. 31, 2015USD ($)
Year ending: [Abstract]
December 31, 2016	$ 30,202
December 31, 2017	25,643
December 31, 2018	22,740
December 31, 2019	21,560
December 31, 2020	15,501
Thereafter	40,255
Total	$ 155,901

Stockholders Equity and Stock52

Stockholders Equity and Stock-Based Compensation (Narrative) (Details) - USD ($)	Jan. 05, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders Equity and Stock-Based Compensation [Line Items]
Treasury Stock, Shares		244,113	244,113
Class B Share Convertible to Class A Share		1
Preferred Stock, Shares Authorized		20,000,000
Preferred Stock, Par Value Per Share		$ 0.01
Preferred Stock, Shares Outstanding		0	0
Share Based Compensation Arrangement By Share Based Payment Additional Shares Made Available		12,817,107
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		5,059,953
Allocated Share-based Compensation Expense		$ 4,400,000	$ 4,400,000	$ 5,200,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount		$ 0	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Award, Award Vesting Period		3 years	3 years	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		5 years	5 years	5 years
Expected Annual Cash Dividend		$ 0.84
Granted, Weighted Average Fair Value		$ 4.59	$ 4.76	$ 4.84
Share-based Payment Award, Options, Vested, Fair Value		$ 3,600,000	$ 4,400,000	$ 6,100,000
Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized		$ 3,000,000
Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition		2 years
Restricted Stock Granted to Board of Directors [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Award, Award Vesting Period		1 year	1 year	1 year
Restricted Stock Units (RSUs) [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Award, Award Vesting Period		2 years
Class A Common Stock [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Common Stock, Shares Authorized		150,000,000	150,000,000
Common Stock, Par Value Per Share		$ 0.01	$ 0.01
Common Stock, Shares Outstanding		24,487,471	24,179,401
Common Stock, Voting Rights		1
Class B Common Stock [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Common Stock, Shares Authorized		50,000,000	50,000,000
Common Stock, Par Value Per Share		$ 0.01	$ 0.01
Common Stock, Shares Outstanding		13,191,845	13,192,845
Common Stock, Voting Rights		10
Maximum [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		8 years	8 years	8 years
Going Private Transaction [Member] | Class A Common Stock [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Common Stock, Voting Rights		1
Going Private Transaction [Member] | Class B Common Stock [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Common Stock, Voting Rights		1
Subsequent Event [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Annual Percentage Increase In Number Of Shares Available For Issuance	1.50%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	565,190
Additional Paid-in Capital [Member]
Stockholders Equity and Stock-Based Compensation [Line Items]
Tax deficiency from the exercise of stock options		$ (2,971,000)	$ (3,211,000)	$ (2,332,000)

Stockholders Equity and Stock53

Stockholders Equity and Stock-Based Compensation (Schedule of Shared-based Payment Award, Stock Options, Valuation Assumptions) (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders Equity and Stock-Based Compensation [Abstract]
Volatility	26.16%	28.96%	31.92%
Expected life of options	3 years	3 years	3 years
Risk-free interest rate	1.15%	0.96%	0.56%
Dividend yield	3.00%	3.00%	3.00%

Stockholders Equity and Stock54

Stockholders Equity and Stock-Based Compensation (Schedule of Share-based Compensation, Stock Options, Activity) (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Payment Award, Options, Outstanding [Roll Forward]
Stock options, Number of Shares, Period Start	3,391,032	3,400,120	3,421,196
Granted, Number of Shares	237,853	946,576	957,525
Exercised, Number of Shares	(284,320)	(158,371)	(79,567)
Cancelled and expired, Number of Shares	(849,255)	(797,293)	(899,034)
Stock options, Number of Shares, Period End	2,495,310	3,391,032	3,400,120
Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Stock options, Weighted Average Exercise Price, Period Start	$ 32.76	$ 35.51	$ 38.61
Granted, Weighted Average Exercise Price	30.87	29.12	27.42
Exercised, Weighted Average Exercise Price	27.51	24.78	22.75
Cancelled and expired, Weighted Average Exercise Price	39.56	41.75	39.84
Stock options, Weighted Average Exercise Price, Period End	$ 30.86	$ 32.76	$ 35.51
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Stock options, Aggregate Intrinsic Value	$ 3,583	$ 4,722	$ 4,488	$ 626
Exercised, Aggregate Intrinsic Value	$ 1,348	$ 754	$ 400

Stockholders Equity and Stock55

Stockholders Equity and Stock-Based Compensation (Schedule of Non-Vested Share Activity) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested [Roll Forward]
Non-vested stock options, Number of Shares, Period Start	1,673,528
Granted, Number of Shares	237,853	946,576	957,525
Vested, Number of Shares	(726,750)
Cancelled, Number of Shares	(193,341)
Non-vested stock options, Number of Shares, Period End	991,290	1,673,528
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Non-vested stock options, Weighted Average Fair Value, Period Start	$ 4.83
Granted, Weighted Average Fair Value	4.59	$ 4.76	$ 4.84
Vested, Weighted Average Fair Value	4.89
Cancelled, Weighted Average Fair Value	4.79
Non-vested stock options, Weighted Average Fair Value, Period End	$ 4.74	$ 4.83

Stockholders Equity and Stock56

Stockholders Equity and Stock-Based Compensation (Stock Options Exercisable And Expected To Vest) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)$ / sharesshares
Stockholders Equity and Stock-Based Compensation [Abstract]
Stock options exercisable, Number of Shares	1,504,020
Stock options expected to vest, Number of Shares	894,966
Stock options exercisable and expected to vest, Number of Shares	2,398,986
Stock options exercisable, Weighted Average Remaining Contractual Life	2 years
Stock options exercisable, Weighted Average Exercise Price | $ / shares	$ 32.01
Stock options exercisable, Aggregate Intrinsic Value | $	$ 2,236
Stock options expected to vest, Weighted Average Remaining Contractual Life	4 years
Stock options expected to vest, Weighted Average Exercise Price | $ / shares	$ 29.08
Stock options expected to vest, Aggregate Intrinsic Value | $	$ 1,242

Stockholders Equity and Stock57

Stockholders Equity and Stock-Based Compensation (Schedule of Share-based Compensation, Restricted Stock Activity) (Details) - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock, Non-vested
Non-vested, Period Start	21,000	21,000
Granted	21,000	21,000
Vested	(21,000)	(21,000)
Non-vested, Period End	21,000	21,000
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock, Weighted Average Fair Value
Non-vested, Weighted Average Fair Value, Period Start	$ 30.61	$ 27.65
Granted, Weighted Average Fair Value	28.98	30.61
Vested, Weighted Average Fair Value	30.61	27.65
Non-vested, Weighted Average Fair Value, Period End	$ 28.98	$ 30.61

Stockholders Equity and Stock58

Stockholders Equity and Stock-Based Compensation Schedule of Share-based Compensation, Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) [Member]	12 Months Ended
	Dec. 31, 2015$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Number of Shares [Roll Forward]
Non-vested, Period Start | shares	0
Granted | shares	105,900
Forfeited | shares	(12,450)
Non-vested, Period End | shares	93,450
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Weighted Average Fair Value
Non-vested, Weighted Average Fair Value, Period Start | $ / shares	$ 0
Granted, Weighted Average Fair Value | $ / shares	30.85
Forfeited, Weighted Average Fair Value | $ / shares	30.92
Non-vested, Weighted Average Fair Value, Period End | $ / shares	$ 30.84

Retirement Plans (Narrative) (D

Retirement Plans (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Retirement Plan [Line Items]
Defined Contribution Plan, Other Than Employee Stock Ownership Plan, Contributions	$ 18,500,000	$ 18,600,000	$ 19,300,000
Employee Stock Ownership Plan (ESOP), Vesting Period	5 years	5 years	5 years
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 0	$ 0	$ 900,000
Employee Supplemental Savings Plan (ESSP) Percentage of Annual Base Compensation	75.00%	75.00%	75.00%
Employee Supplemental Savings Plan (ESSP) Percentage of Bonus	100.00%	100.00%	100.00%
Employee Supplemental Savings Plan (ESSP), Employee Contribution	$ 2,800,000	$ 3,000,000	$ 3,200,000
Defined Benefit Plan, Actual Plan Asset Allocations	100.00%	100.00%
Defined Benefit Plan, Benefit Obligation	$ 1,100,000	$ 1,300,000
Class A Common Stock [Member]
Retirement Plan [Line Items]
Employee Stock Ownership Plan (ESOP), Shares Contributed to ESOP	0	0	31,653

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Non-current Provision (Benefit) for income taxes arising from Cancellation of Vested Stock Options Allocated to Equity and Valuation Differences between Grant and Vesting Dates on Restricted Stock Allocated to Equity	$ (3)	$ (3.3)	$ (2.4)
Non-current Provision (Benefit) for Income Taxes related to Liabilities for Uncertain Tax Positions	(0.3)	(0.4)	(0.1)
Income Taxes Paid, Net of Refunds	6.4	14.3	14.9
Tax Benefits, Nonqualified Stock Options and Disqualifying Dispositions of Incentive Stock Options	0.1
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	0.4	0.6	0.9
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	0.1	$ 0.2	$ 0.2
Settlement With Taxing Authority [Member]
Income Tax Contingency [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	0.3
State [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 9.2

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income before Income Tax, Domestic and Foreign) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Domestic									$ 85,665	$ 79,238	$ 6,768
Foreign									(311)	(137)	(215)
INCOME FROM OPERATIONS BEFORE INCOME TAXES AND EQUITY METHOD INVESTMENTS	$ 22,625	$ 22,353	$ 20,879	$ 19,497	$ 23,621	$ 26,492	$ 12,929	$ 16,059	$ 85,354	$ 79,101	$ 6,553

Income Taxes (Schedule of Compo

Income Taxes (Schedule of Components of Income Tax Expense (Benefit)) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current provision:
Federal	$ 2,714,000	$ 10,375,000	$ 18,702,000
State	1,247,000	2,499,000	4,011,000
Foreign	77,000	160,000	86,000
Current provision	4,038,000	13,034,000	22,799,000
Deferred provision (benefit):
Federal	27,817,000	17,739,000	(6,557,000)
State	5,825,000	4,477,000	(1,858,000)
Deferred provision (benefit)	33,642,000	22,216,000	(8,415,000)
Non-current provision (benefit) resulting from allocating tax benefits directly to additional paid in capital and changes in liabilities:
Federal	(2,568,000)	(2,755,000)	(2,009,000)
State	(746,000)	(970,000)	(522,000)
Foreign	0	0	(11,000)
Non-current provision (benefit) resulting from allocating tax benefits directly to additional paid in capital and changes in liabilities	(3,314,000)	(3,725,000)	(2,542,000)
Provision for income taxes	$ 34,366,000	$ 31,525,000	$ 11,842,000

Income Taxes (Schedule of Effec

Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Statutory U.S. Federal tax rate	35.00%	35.00%	35.00%
Increase (decrease) in tax rate resulting from:
State taxes—net of Federal benefit	4.80%	5.00%	18.60%
Excess executive compensation	0.50%	1.30%	16.70%
Section 199 deductions	(0.40%)	(0.60%)	(6.50%)
Deferred compensation (ESSP)	0.20%	(0.70%)	(24.60%)
Goodwill impairment	0.00%	0.00%	200.10%
Tax basis deduction of investment	0.00%	0.00%	(15.30%)
Provisions of American Taxpayer Relief Act of 2012	0.00%	0.00%	(10.30%)
Acquisition working capital settlement	0.00%	0.00%	(5.00%)
Other, net	0.10%	0.00%	(0.70%)
Effective tax rate	40.20%	40.00%	208.00%

Income Taxes (Schedule of Defer

Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Gross deferred tax liabilities:
Goodwill and other assets	$ 111,156	$ 86,242
Unbilled receivables	19,154	14,549
Property and equipment	4,554	3,931
Total	134,864	104,722
Gross deferred tax assets:
Retirement and other liabilities	(29,000)	(31,851)
Allowance for potential contract losses and other contract reserves	(3,429)	(3,911)
Federal and state operating loss carryforwards	(400)	(441)
Total	(32,829)	(36,203)
Net deferred tax liabilities	$ 102,035	$ 68,519

Income Taxes (Schedule of Unrec

Income Taxes (Schedule of Unrecognized Tax Benefits Roll Forward) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Gross Unrecognized Tax Benefits, Period Start	$ 785,000	$ 1,207,000	$ 1,376,000
Lapse in statute of limitations	(266,000)	(575,000)	(307,000)
Increases in tax positions for prior years	0	80,000	95,000
Decreases in tax positions for prior years	0	(13,000)	(26,000)
Increases in tax positions for current year	0	86,000	69,000
Gross Unrecognized Tax Benefits, Period End	$ 519,000	$ 785,000	$ 1,207,000

Business Segment and Geograph66

Business Segment and Geographic Area Information (Narrative) (Details) - reportable_segment	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Number of Reportable Segments	1
Revenues [Member] | UNITED STATES
Segment Reporting Information [Line Items]
Percentage	99.90%	99.70%	99.80%
Revenues [Member] | Non-US [Member]
Segment Reporting Information [Line Items]
Percentage	0.10%	0.30%	0.20%
Revenues [Member] | U.S. Army Tank-Automotive Armament Command (TACOM) [Member]
Segment Reporting Information [Line Items]
Percentage	5.60%	7.50%	19.40%
Revenues [Member] | U.S. government under prime contracts and subcontracts [Member]
Segment Reporting Information [Line Items]
Percentage	98.90%	98.90%	99.00%

Divestiture of ManTech Cyber 67

Divestiture of ManTech Cyber Solutions and Investment in CounterTack Inc. (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Jul. 13, 2015
Noncash or Part Noncash Divestitures [Line Items]
Gain on Disposition of Business	$ 1,692,000	$ 0	$ 0
CounterTack Inc. [Member]
Noncash or Part Noncash Divestitures [Line Items]
Payments to Acquire Other Investments	3,800,000
ManTech Cyber Solutions International [Member]
Noncash or Part Noncash Divestitures [Line Items]
Disposal Group, Including Discontinued Operation, Assets				$ 5,500,000
Disposal Group, Including Discontinued Operation, Liabilities				$ 1,700,000
Disposal Group, Transactions Costs	1,200,000
ManTech Cyber Solutions International [Member] | CounterTack Inc. [Member]
Noncash or Part Noncash Divestitures [Line Items]
Noncash or Part Noncash Divestiture, Amount of Consideration Received	$ 6,700,000

Quarterly Financial Informati68

Quarterly Financial Information (Unaudited) (Schedule of Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Line Items]
Revenues	$ 402,401	$ 393,008	$ 384,378	$ 370,330	$ 411,367	$ 447,200	$ 463,381	$ 452,033	$ 1,550,117	$ 1,773,981	$ 2,310,072
Operating income	22,808	21,120	21,112	19,846	23,972	26,732	24,070	20,042	84,886	94,816	22,243
Income from operations before income taxes and equity method investments	22,625	22,353	20,879	19,497	23,621	26,492	12,929	16,059	85,354	79,101	6,553
Net income	$ 13,891	$ 13,028	$ 12,450	$ 11,758	$ 14,465	$ 15,487	$ 7,708	$ 9,634	$ 51,127	$ 47,294	$ (6,149)
Class A Common Stock [Member]
Quarterly Financial Information Disclosure [Line Items]
Basic weighted average common shares outstanding	24,393	24,341	24,325	24,206	24,115	24,061	24,023	23,988	24,317	24,047	23,913
Basic earnings per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.42	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Diluted weighted average common shares outstanding	24,513	24,406	24,426	24,359	24,191	24,126	24,092	24,057	24,426	24,117	23,913
Diluted earnings per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.41	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Class B Common Stock [Member]
Quarterly Financial Information Disclosure [Line Items]
Basic weighted average common shares outstanding	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193
Basic earnings per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.42	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)
Diluted weighted average common shares outstanding	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193	13,193
Diluted earnings per share	$ 0.37	$ 0.35	$ 0.33	$ 0.31	$ 0.39	$ 0.41	$ 0.21	$ 0.26	$ 1.36	$ 1.27	$ (0.17)

Schedule II (Valuation and Qual

Schedule II (Valuation and Qualifying Accounts) (Details) - USD ($)		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period		$ 9,830,000	$ 10,036,000	$ 9,449,000
Charged to Costs and Expenses		0	0	0
Deductions		(552,000)	(165,000)	0
Other	[1]	(805,000)	(41,000)	587,000
Balance at End of Period		8,473,000	9,830,000	10,036,000
Deferred Tax Asset Valuation
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period		64,000	191,000	0
Charged to Costs and Expenses		0	0	191,000
Deductions		0	(127,000)	0
Other		(64,000)	0	0
Balance at End of Period		$ 0	$ 64,000	$ 191,000
[1]	Other represents doubtful account reserves released or recorded as part of net revenues for estimated customer disallowances.