CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONSOLIDATED STATEMENTS OF OPERATIONS
Consulting fee revenue	$ 152,453us-gaap_ContractsRevenue	$ 137,249us-gaap_ContractsRevenue
Reimbursable expenses	19,127us-gaap_ReimbursementRevenue	12,764us-gaap_ReimbursementRevenue
Total revenue	171,580us-gaap_Revenues	150,013us-gaap_Revenues
Cost of services	86,689us-gaap_CostOfServices	78,590us-gaap_CostOfServices
Reimbursable expenses	19,127us-gaap_CostOfReimbursableExpense	12,764us-gaap_CostOfReimbursableExpense
Total direct expenses	105,816us-gaap_CostOfRevenue	91,354us-gaap_CostOfRevenue
Gross profit	65,764us-gaap_GrossProfit	58,659us-gaap_GrossProfit
Selling, general and administrative expenses	59,565	52,659
Equity in losses of affiliate	183
Operating profit	6,016us-gaap_OperatingIncomeLoss	6,000us-gaap_OperatingIncomeLoss
Interest and related financing fees, net	3,574us-gaap_InterestIncomeExpenseNet	5,076us-gaap_InterestIncomeExpenseNet
Earnings before income taxes	2,442	924
Income tax expense	1,163us-gaap_IncomeTaxExpenseBenefit	631us-gaap_IncomeTaxExpenseBenefit
Net earnings	1,279	293
Less: net earnings - noncontrolling interests	184	240
Net earnings attributable to Hill International, Inc.	$ 1,095us-gaap_NetIncomeLoss	$ 53us-gaap_NetIncomeLoss
Basic earnings per common share - Hill International, Inc. (in dollars per share)	$ 0.02us-gaap_EarningsPerShareBasic
Basic weighted average common shares outstanding (in shares)	50,373	39,795
Diluted earnings per common share - Hill International, Inc. (in dollars per share)	$ 0.02us-gaap_EarningsPerShareDiluted
Diluted weighted average common shares outstanding (in shares)	50,637	40,602

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