Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenue:
Software license	$ 19,314us-gaap_LicensesRevenue	$ 17,107us-gaap_LicensesRevenue
Services	101,203us-gaap_SalesRevenueServicesNet	86,913us-gaap_SalesRevenueServicesNet
Hardware and other	13,006manh_HardwareRevenueAndOther	9,543manh_HardwareRevenueAndOther
Total revenue	133,523us-gaap_SalesRevenueNet	113,563us-gaap_SalesRevenueNet
Costs and expenses:
Cost of license	2,906us-gaap_LicenseCosts	1,613us-gaap_LicenseCosts
Cost of services	44,784us-gaap_CostOfServices	38,460us-gaap_CostOfServices
Cost of hardware and other	10,547manh_CostOfHardwareAndOther	7,479manh_CostOfHardwareAndOther
Research and development	13,556us-gaap_ResearchAndDevelopmentExpense	11,803us-gaap_ResearchAndDevelopmentExpense
Sales and marketing	11,847us-gaap_SellingAndMarketingExpense	12,020us-gaap_SellingAndMarketingExpense
General and administrative	11,238us-gaap_GeneralAndAdministrativeExpense	10,649us-gaap_GeneralAndAdministrativeExpense
Depreciation and amortization	1,781us-gaap_DepreciationAndAmortization	1,488us-gaap_DepreciationAndAmortization
Total costs and expenses	96,659us-gaap_CostsAndExpenses	83,512us-gaap_CostsAndExpenses
Operating income	36,864us-gaap_OperatingIncomeLoss	30,051us-gaap_OperatingIncomeLoss
Other income (loss), net	262us-gaap_OtherNonoperatingIncomeExpense	(233)us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	37,126	29,818
Income tax provision	13,922us-gaap_IncomeTaxExpenseBenefit	11,106us-gaap_IncomeTaxExpenseBenefit
Net income	$ 23,204us-gaap_NetIncomeLoss	$ 18,712us-gaap_NetIncomeLoss
Basic earnings per share	$ 0.31us-gaap_EarningsPerShareBasic	$ 0.25us-gaap_EarningsPerShareBasic
Diluted earnings per share	$ 0.31us-gaap_EarningsPerShareDiluted	$ 0.24us-gaap_EarningsPerShareDiluted
Weighted average number of shares:
Basic	73,979	75,817
Diluted	74,607	76,795

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