Huron Consulting (HURN) 10-K 28 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 21, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	Huron Consulting Group Inc.
Trading Symbol	HURN
Entity Central Index Key	1,289,848
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		22,180,119
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 934,900,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 16,909	$ 17,027
Receivables from clients, net	101,778	94,246
Costs in Excess of Billings, Current	57,618	51,290
Income tax receivable	4,039	4,211
Prepaid Expense and Other Assets, Current	10,951	13,308
Total current assets	191,295	180,082
Property and equipment, net	45,541	32,434
Deferred Tax Assets, Net, Noncurrent	16,752	0
Long-term investment	39,904	34,675
Other non-current assets	25,375	24,814
Intangible assets, net	72,311	81,348
Goodwill	645,750	799,862
Total assets	1,036,928	1,153,215
Current liabilities:
Accounts payable	9,194	7,273
Accrued expenses and other current liabilities	20,144	19,788
Accrued payroll and related benefits	73,698	82,669
Business Combination, Contingent Consideration, Liability, Current	8,515	1,985
Deferred revenues	27,916	24,053
Total current liabilities	139,467	135,768
Non-current liabilities:
Deferred compensation and other liabilities	20,895	24,171
Business Combination, Contingent Consideration, Liability, Noncurrent	14,313	6,842
Long-term debt, net of current portion	342,507	292,065
Deferred lease incentives	15,333	10,703
Deferred income taxes, net	1,097	35,633
Total non-current liabilities	394,145	369,414
Commitments and contingencies
Stockholders’ equity
Common Stock, Value, Issued	241	235
Treasury Stock, Value	121,994	113,195
Additional paid-in capital	434,256	405,895
Retained earnings	180,443	351,483
Accumulated other comprehensive income	10,370	3,615
Total stockholders’ equity	503,316	648,033
Total liabilities and stockholders’ equity	$ 1,036,928	$ 1,153,215

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Common stock, par value (in USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	24,560,468	24,126,118
Treasury stock, shares	2,443,577	2,408,343

Consolidated Statements of Earn

Consolidated Statements of Earnings and Other Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues and reimbursable expenses:
Revenues	$ 732,570	$ 726,272	$ 699,010
Reimbursable expenses	75,175	71,712	70,013
Total revenues and reimbursable expenses	807,745	797,984	769,023
Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses):
Direct costs	454,806	437,556	401,915
Amortization of intangible assets and software development costs	10,932	15,140	16,788
Reimbursable expenses	75,436	71,749	69,932
Total direct costs and reimbursable expenses	541,174	524,445	488,635
Operating expenses and other operating gains:
Selling, general and administrative expenses	175,364	160,204	157,902
Restructuring charges (1)	6,246	9,592	3,329
Litigation and other losses (gains), net	1,111	(1,990)	(9,476)
Depreciation and amortization	38,213	31,499	25,135
Goodwill, Impairment Loss	253,093	0	0
Total operating expenses and other losses (gains), net	474,027	199,305	176,890
Operating income (loss)	(207,456)	74,234	103,498
Other income (expense), net
Interest Expense Net Of Interest Income	18,613	16,274	18,136
Other Nonoperating Income (Expense)	3,565	1,197	(1,797)
Nonoperating Income (Expense)	(15,048)	(15,077)	(19,933)
Income (loss) from continuing operations before taxes	(222,504)	59,157	83,565
Income tax expense (benefit)	(51,999)	19,677	21,670
Net income (loss) from continuing operations	(170,505)	39,480	61,895
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	388	(1,863)	(2,843)
Net income (loss)	$ (170,117)	$ 37,617	$ 59,052
Net earnings per basic share:
Net income from continuing operations, per basic share (in USD per share)	$ (7.95)	$ 1.87	$ 2.80
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	0.02	(0.09)	(0.13)
Net income, per basic share (in USD per share)	(7.93)	1.78	2.67
Net earnings per diluted share:
Net income from continuing operations, per diluted share (in USD per share)	(7.95)	1.84	2.74
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	0.02	(0.08)	(0.13)
Net income, per diluted share (in USD per share)	$ (7.93)	$ 1.76	$ 2.61
Weighted average shares used in calculating earnings per share:
Basic (shares)	21,439	21,084	22,136
Diluted (shares)	21,439	21,424	22,600
Comprehensive income (loss):
Net income (loss)	$ (170,117)	$ 37,617	$ 59,052
Foreign currency translation adjustments, net of tax	1,602	64	1,817
Unrealized gain (loss) on investment, net of tax	4,724	(97)	4,435
Unrealized gain (loss) on cash flow hedging instruments, net of tax	429	63	(12)
Other comprehensive income	6,755	30	6,240
Comprehensive income (loss)	$ (163,362)	$ 37,647	$ 65,292

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2014	$ 600,634	$ 241	$ (94,074)	$ 442,308	$ 254,814	$ (2,655)
Beginning balance, shares at Dec. 31, 2014		(24,115,593)	(2,109,316)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	65,292				59,052	6,240
Share-based compensation	22,484			22,484
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations		$ 5	$ (2,506)	2,501
Restricted stock awards, net of cancellations, shares		(504,955)	(42,797)
Business acquisition	2,204	$ 0		2,204
Business acquisition, shares		28,486
Shares redeemed for employee tax withholdings	(7,154)		$ (7,154)
Shares redeemed for employee tax withholdings, shares			(109,967)
Income tax benefit on share-based compensation	3,456			3,456
Share repurchases	(34,591)	$ (5)		(34,586)
Share repurchases, shares		(583,880)
Ending balance at Dec. 31, 2015	652,325	$ 241	$ (103,734)	438,367	313,866	3,585
Ending balance, shares at Dec. 31, 2015		(24,065,154)	(2,262,080)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	37,647				37,617	30
Share-based compensation	17,929			17,929
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations		$ 4	$ (4,508)	4,504
Restricted stock awards, net of cancellations, shares		(390,348)	(70,419)
Stock Issued During Period, Value, Stock Options Exercised	123	$ 0		123
Exercise of stock options, shares		4,706
Shares redeemed for employee tax withholdings	(4,953)		$ (4,953)
Shares redeemed for employee tax withholdings, shares			(88,414)
Income tax benefit on share-based compensation	227			227
Share repurchases	(55,265)	$ (10)		(55,255)
Share repurchases, shares		(982,192)
Ending balance at Dec. 31, 2016	648,033	$ 235	$ (113,195)	405,895	351,483	3,615
Ending balance, shares at Dec. 31, 2016		(23,478,016)	(2,420,913)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	(163,362)				(170,117)	6,755
Share-based compensation	$ 14,419			14,419
Issuance of common stock in connection with:
Restricted stock awards, net of cancellations		$ 4	$ (3,953)	3,949
Restricted stock awards, net of cancellations, shares		(399,248)	(58,211)
Exercise of stock options, shares	0
Business acquisition	$ 9,560	$ 2		9,558
Business acquisition, shares		221,558
Shares redeemed for employee tax withholdings	(4,846)		$ (4,846)
Shares redeemed for employee tax withholdings, shares			(112,011)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | ASU201609 [Member]	0			435	(435)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | ASU2018-02 [Member]	(488)				(488)
Ending balance at Dec. 31, 2017	$ 503,316	$ 241	$ (121,994)	$ 434,256	$ 180,443	$ 10,370
Ending balance, shares at Dec. 31, 2017		(24,098,822)	(2,591,135)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Cash flows from operating activities:
Net income (loss)	$ (170,117)	$ 37,617	$ 59,052
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	50,089	46,816	58,053
Share-based compensation	14,838	16,577	21,487
Amortization of debt discount and issuance costs	10,203	9,609	9,329
Goodwill, Impairment Loss	253,093	0	0
Allowances for doubtful accounts and unbilled services	3,217	4,250	1,025
Deferred income taxes	(53,753)	1,189	6,353
(Gain) loss on sale of businesses	(931)	0	2,303
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	(1,111)	1,990	1,126
Changes in operating assets and liabilities, net of acquisitions and divestitures:
(Increase) decrease in receivables from clients	1,650	1,440	(2,836)
(Increase) decrease in unbilled services	(4,332)	2,443	31,696
(Increase) decrease in current income tax receivable / payable, net	210	(4,410)	8,818
(Increase) decrease in other assets	(366)	11,904	(14,742)
Increase (decrease) in accounts payable and accrued liabilities	3,732	(3,144)	8,805
Increase (decrease) in accrued payroll and related benefits	(10,966)	3,044	(25,221)
Increase (decrease) in deferred revenues	2,117	3,898	4,859
Net cash provided by operating activities	99,795	129,243	167,855
Cash flows from investing activities:
Purchases of property and equipment, net	(24,402)	(13,936)	(18,571)
Investment in life insurance policies	(1,826)	(2,035)	(5,804)
Proceeds from Life Insurance Policies	2,889	0	0
Purchases of businesses, net of cash acquired	(106,915)	(69,133)	(339,966)
Purchases of convertible debt investment	0	0	(15,438)
Capitalization of internally developed software	(1,370)	(1,086)	(866)
Proceeds from note receivable	1,177	0	0
Proceeds from Divestiture of Businesses	1,499	(446)	108,487
Net cash used in investing activities	(128,948)	(86,636)	(272,158)
Cash flows from financing activities:
Proceeds from exercises of stock options	0	123	0
Shares redeemed for employee tax withholdings	(4,846)	(4,953)	(7,154)
Share repurchases	0	(55,265)	(34,591)
Proceeds from borrowings under credit facility	277,500	200,000	314,000
Repayments of debt	(240,745)	(224,000)	(365,750)
Payments for debt issuance costs	(408)	0	0
Payments for capital lease obligations	0	0	(48)
Deferred acquisition payments	(2,680)	0	0
Net cash provided by (used in) financing activities	28,821	(84,095)	(93,543)
Effect of exchange rate changes on cash	214	78	(589)
Net decrease in cash and cash equivalents	(118)	(41,410)	(198,435)
Cash and cash equivalents at beginning of the period	17,027	58,437	256,872
Cash and cash equivalents at end of the period	16,909	17,027	58,437
Non-cash investing and financing activities:
Property and equipment expenditures included in accounts payable and accrued expenses	1,567	4,461	2,089
Notes Assumed	5,113	0	0
Contingent consideration related to business acquisitions	15,489	8,754	2,963
Common stock issued related to business acquisitions	9,560	0	2,204
Cash paid during the year for:
Interest	9,068	6,470	9,274
Income taxes	$ 5,399	$ 24,584	$ 10,955

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Description of Business	Description of Business Huron is a global professional services firm committed to achieving sustainable results in partnership with its clients. We bring a depth of expertise in strategy, technology, operations, advisory services, and analytics to drive lasting and measurable results in the healthcare, higher education, life sciences and commercial sectors.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The accompanying consolidated financial statements reflect the financial position at December 31, 2017 and 2016 , and the results of operations and cash flows for the years ended December 31, 2017 , 2016 , and 2015 . The consolidated financial statements include the accounts of Huron Consulting Group Inc. and its subsidiaries, all of which are wholly-owned. All intercompany balances and transactions have been eliminated in consolidation. During the second quarter of 2017, we recorded a non-cash pretax goodwill impairment charge of $209.6 million related to our Healthcare reporting unit. During the fourth quarter of 2017, we identified that our calculation of the non-deductible portion of this goodwill impairment charge erroneously excluded a portion of goodwill that was related to an acquisition completed in 2008 that has since been divested. To correct this error, in the fourth quarter of 2017, we recorded a $1.5 million decrease to our non-cash pretax goodwill impairment charge with an offsetting $1.5 million increase to our goodwill balance. We also recorded a $1.5 million decrease to our income tax benefit with an offsetting $1.5 million increase to our deferred tax asset balance. This error had no impact on our consolidated net loss from continuing operations, and we concluded that the impact of the error was not material for the second, third, or fourth quarter financial statements, or the financial statements for the year ended December 31, 2017. During the fourth quarter of 2017, we identified an error on our previously reported consolidated balance sheets as of June 30, 2017 and September 30, 2017 related to the classification of deferred tax assets and liabilities. We incorrectly netted $1.5 million of deferred tax liabilities related to certain jurisdictions with the deferred tax assets of unrelated jurisdictions as of June 30, 2017 and September 30, 2017. This error has been corrected as of December 31, 2017. This error had no impact on our statement of operations, and we concluded that the impact of the error was not material to the second and third quarter financial statements or the financial statements for the year ended December 31, 2017. On December 31, 2015, we sold our Huron Legal segment to a third party. The operations of our Huron Legal segment have been classified as discontinued operations in our consolidated statements of operations for all periods presented. As of December 31, 2017 and 2016 , no assets or liabilities of the disposed business remained on our consolidated balance sheet. See Note 3 "Discontinued Operations" for additional information on the divestiture of our Huron Legal segment. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and accompanying disclosures. Actual results may differ from these estimates and assumptions. Revenue Recognition Revenue is recognized when persuasive evidence of an arrangement exists, the related services are provided, the price is fixed or determinable, and collectability is reasonably assured. We generate the majority of our revenues from providing professional services under four types of billing arrangements: fixed-fee (including software license revenue), time-and-expense, performance-based, and software support and maintenance and subscriptions. In fixed-fee billing arrangements, we agree to a pre-established fee in exchange for a predetermined set of professional services. We set the fees based on our estimates of the costs and timing for completing the engagements. We generally recognize revenues under fixed-fee billing arrangements using a proportionate performance approach, which is based on work completed to-date versus our estimates of the total services to be provided under the engagement. Contracts within our Studer Group solution are fixed-fee partner contracts with multiple deliverables, which primarily consist of coaching services, as well as seminars, materials and software products (“Partner Contracts”). Revenues for coaching services and software products are generally recognized on a straight-line basis over the length of the contract. All other revenues under Partner Contracts are recognized at the time the service is provided. Estimates of total engagement revenues and cost of services are monitored regularly during the term of the engagement. If our estimates indicate a potential loss, such loss is recognized in the period in which the loss first becomes probable and reasonably estimable. We also generate revenues from software licenses for our revenue cycle management software and research administration and compliance software. Licenses for our revenue cycle management software are sold only as a component of our consulting projects, and the services we provide are essential to the functionality of the software. Therefore, revenues from these software licenses are recognized over the term of the related consulting services contract. License revenue from our research administration and compliance software is generally recognized in the month in which the software is delivered. Time-and-expense billing arrangements require the client to pay based on the number of hours worked by our revenue-generating professionals at agreed upon rates. Time-and-expense arrangements also include certain speaking engagements, conferences, and publication orders purchased by our clients outside of Partner Contracts within our Studer Group solution. We recognize revenues under time-and-expense arrangements as the related services or publications are provided. In performance-based billing arrangements, fees are tied to the attainment of contractually defined objectives. We enter into performance-based engagements in essentially two forms. First, we generally earn fees that are directly related to the savings formally acknowledged by the client as a result of adopting our recommendations for improving operational and cost effectiveness in the areas we review. Second, we have performance-based engagements in which we earn a success fee when and if certain predefined outcomes occur. We do not recognize revenues under performance-based billing arrangements until all related performance criteria are met. Clients that have purchased one of our software licenses can pay an annual fee for software support and maintenance. We also generate subscription revenue from our cloud-based analytic tools and solutions. Software support and maintenance and subscription-based revenues are recognized ratably over the support or subscription period, which ranges from one to three years. These fees are billed in advance and included in deferred revenues until recognized. We have arrangements with clients in which we provide multiple elements of services under one engagement contract. Revenues under these types of arrangements are allocated to each element based on the element’s fair value and recognized pursuant to the criteria described above. Provisions are recorded for the estimated realization adjustments on all engagements, including engagements for which fees are subject to review by the bankruptcy courts. Expense reimbursements that are billable to clients are included in total revenues and reimbursable expenses, and typically an equivalent amount of reimbursable expenses are included in total direct costs and reimbursable expenses. Reimbursable expenses are primarily recognized as revenue in the period in which the expense is incurred. Subcontractors that are billed to clients at cost are also included in reimbursable expenses. When billings do not specifically identify reimbursable expenses, we allocate the portion of the billings equivalent to these expenses to reimbursable expenses. Differences between the timing of billings and the recognition of revenue are recognized as either unbilled services or deferred revenues in the accompanying consolidated balance sheets. Revenues recognized for services performed but not yet billed to clients are recorded as unbilled services. Client prepayments and retainers are classified as deferred revenues and recognized over future periods as earned in accordance with the applicable engagement agreement. Allowances for Doubtful Accounts and Unbilled Services We maintain allowances for doubtful accounts and for services performed but not yet billed based on several factors, including the estimated cash realization from amounts due from clients, an assessment of a client’s ability to make required payments, and the historical percentages of fee adjustments and write-offs by age of receivables and unbilled services. The allowances are assessed by management on a regular basis. These estimates may differ from actual results. If the financial condition of a client deteriorates in the future, impacting the client’s ability to make payments, an increase to our allowance might be required or our allowance may not be sufficient to cover actual write-offs. We record the provision for doubtful accounts and unbilled services as a reduction in revenue to the extent the provision relates to fee adjustments and other discretionary pricing adjustments. To the extent the provision relates to a client’s inability to make required payments on accounts receivables, we record the provision to selling, general and administrative expenses. Direct Costs and Reimbursable Expenses Direct costs and reimbursable expenses consist primarily of revenue-generating employee compensation and their related benefits and share-based compensation costs, as well as commissions, the cost of outside consultants or subcontractors assigned to revenue-generating activities, technology costs, other third-party costs directly attributable to our revenue-generating activities, and direct expenses to be reimbursed by clients. Direct costs and reimbursable expenses incurred on engagements are expensed in the period incurred. Cash and Cash Equivalents We consider all highly liquid investments, including overnight investments and commercial paper, with original maturities of three months or less to be cash equivalents. Concentrations of Credit Risk To the extent receivables from clients become delinquent, collection activities commence. No single client balance is considered large enough to pose a material credit risk. The allowances for doubtful accounts and unbilled services are based upon the expected ability to collect accounts receivable and bill and collect unbilled services. Management does not anticipate incurring losses on accounts receivable in excess of established allowances. See Note 18 “Segment Information” for concentration of accounts receivable and unbilled services. We hold our cash in accounts at multiple third-party financial institutions. These deposits, at times, may exceed federally insured limits. We review the credit ratings of these financial institutions, regularly monitor the cash balances in these accounts, and adjust the balances as appropriate. However, these cash balances could be impacted if the underlying financial institutions fail or are subject to other adverse conditions in the financial markets. Long-term Investment Our long-term investment consists of our convertible debt investment in Shorelight Holdings, LLC. We classified the investment as available-for-sale at the time of purchase and reevaluate such classification as of each balance sheet date. The investment is carried at fair value with unrealized holding gains and losses reported in other comprehensive income. If the investment is in an unrealized loss position, we assess whether the investment is other than temporarily impaired. We consider impairments to be other than temporary if they are related to significant credit deterioration or if it is likely we will sell the security before the recovery of its cost basis. We have not identified any other than temporary impairments for our convertible debt investment. In the event there are realized gains and losses or declines in value judged to be other than temporary, we will record the amount in earnings. See Note 12 “Fair Value of Financial Instruments” for further information on our convertible debt investment. Fair Value of Financial Instruments See Note 12 “Fair Value of Financial Instruments” for the accounting policies used to measure the fair value of our financial assets and liabilities that are measured at fair value on a recurring basis. Property and Equipment Property and equipment are recorded at cost, less accumulated depreciation. Depreciation of property and equipment is computed on a straight-line basis over the estimated useful lives of the assets. Software, computers, and related equipment are depreciated over an estimated useful life of two to four years. Furniture and fixtures are depreciated over five years. Aircraft are depreciated over ten years. Leasehold improvements are amortized over the lesser of the estimated useful life of the asset or the initial term of the lease. Software Development Costs We incur internal and external software development costs related to our cloud computing applications and software for internal use. We capitalize these software development costs incurred during the application development stage. Costs related to preliminary project activities and post implementation activities are expensed as incurred. Once the project is substantially complete and ready for its intended use these costs are amortized on a straight-line basis over the technology's estimated useful life. Acquired technology assets are initially recorded at fair value and amortized on a straight-line basis over the estimated useful life. We also incur internal and external software development costs related to our software products that will be sold, leased, or otherwise marketed. We expense these software development costs until technological feasibility has been established. Thereafter and until the software is available for general release to customers, these software development costs are capitalized and subsequently reported at the lower of unamortized cost or net realizable value. These capitalized development costs are amortized in proportion to current and future revenue for each product with an annual minimum equal to the straight-line amortization over the remaining estimated economic life of the product. We classify capitalized software development costs as other non-current assets on our consolidated balance sheet. Unamortized capitalized software development costs were $2.0 million and $1.4 million at December 31, 2017 and 2016 , respectively. During the years ended December 31, 2017 , 2016 , and 2015 , we amortized $0.8 million , $1.1 million , and $1.0 million , respectively, of capitalized software development costs. Intangible Assets Other Than Goodwill Identifiable intangible assets are amortized over their expected useful lives using a method that reflects the economic benefit expected to be derived from the assets or on a straight-line basis. We evaluate the recoverability of intangible assets periodically by taking into account events or circumstances that may warrant revised estimates of useful lives or that indicate the asset may be impaired. Impairment of Long-Lived Assets Long-lived assets, including property and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Events relating to recoverability may include significant unfavorable changes in business conditions, recurring losses, or a significant decline in forecasted operating results over an extended period of time. We evaluate the recoverability of long-lived assets based on forecasted undiscounted cash flows. In connection with the goodwill impairment tests performed for the Healthcare and Enterprise Solutions and Analytics reporting units in 2017, which resulted in non-cash goodwill impairment charges, we performed impairment tests on the long-lived assets allocated to the asset groups within the Healthcare and Enterprise Solutions and Analytics reporting units. Based on the impairment tests performed, we concluded that the long-lived assets allocated to the asset groups were not impaired. No impairment charges for long-lived assets were recorded in 2017, 2016 , or 2015 . Goodwill For acquisitions accounted for as a business combination, goodwill represents the excess of the cost over the fair value of the net assets acquired. We are required to test goodwill for impairment, at the reporting unit level, annually and when events or circumstances indicate the fair value of a reporting unit may be below its carrying value. A reporting unit is an operating segment or one level below an operating segment (referred to as a component) to which goodwill is assigned when initially recorded. We assign goodwill to reporting units based on our integration plans and the expected synergies resulting from the acquisition. We have six reporting units: Healthcare, Education, Business Advisory, Enterprise Solutions and Analytics, Strategy and Innovation, and Life Sciences. The Business Advisory, Enterprise Solutions and Analytics, Strategy and Innovation, and Life Sciences reporting units make up our Business Advisory operating segment. We test goodwill for impairment annually and whenever events or circumstances make it more likely than not that an impairment may have occurred. We perform our annual goodwill impairment test as of November 30 and monitor for interim triggering events on an ongoing basis. In 2017, we performed three goodwill impairment tests: an interim impairment test on our Healthcare reporting unit in the second quarter of 2017; an interim impairment test on our Education and Life Sciences reporting units as a result of our segment reorganization in the second quarter of 2017; and the annual impairment test on all reporting units in the fourth quarter of 2017. As a result of these tests, we recorded total non-cash pretax goodwill impairment charges of $253.1 million . No goodwill impairment charges were recorded in 2016 or 2015. See Note 5 "Goodwill and Intangible Assets" for additional information regarding our interim and annual goodwill impairment tests, and the non-cash goodwill impairment charges recorded in 2017. Business Combinations We use the acquisition method of accounting for business combinations . Each acquired company’s operating results are included in our consolidated financial statements starting on the date of acquisition. The purchase price is equivalent to the fair value of consideration transferred. Tangible and identifiable intangible assets acquired and liabilities assumed are recorded at fair value as of the acquisition date. Goodwill is recognized for the excess of purchase price over the net fair value of tangible and intangible assets acquired and liabilities assumed. Contingent consideration, which is primarily based on the business achieving certain performance targets, is recognized at its fair value on the acquisition date, and changes in fair value are recognized in earnings until settled. Refer to Note 12 “Fair Value of Financial Instruments” for further information regarding our contingent acquisition liability balances. Deferred Lease Incentives We record the portion of the deferred lease incentive liability that we expect to recognize over a period greater than one year as a non-current liability. The non-current portion of the deferred lease incentive liability totaled $15.3 million and $10.7 million at December 31, 2017 and 2016 , respectively, and was primarily generated from tenant improvement allowances and rent abatement. Deferred lease incentives are amortized on a straight-line basis over the life of the lease. The portion of the deferred lease incentive corresponding to the rent payments that will be paid within 12 months of the balance sheet date is classified as a current liability. We monitor the classification of such liabilities based on the expectation of their utilization periods. Income Taxes Current tax liabilities and assets are recognized for the estimated taxes payable or refundable, respectively, on the tax returns for the current year. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. To the extent that deferred tax assets will not likely be recovered from future taxable income, a valuation allowance is established against such deferred tax assets. Refer to Note 16 "Income Taxes" for information on the impact of the Tax Cuts and Jobs Act of 2017 ("2017 Tax Reform") enacted in the fourth quarter on our consolidated financial statements. Share-Based Compensation Share-based compensation cost is measured based on the grant date fair value of the respective awards. We generally recognize share-based compensation ratably using the straight-line attribution method; however, for those awards with performance criteria and graded vesting features, we use the graded vesting attribution method. It is our policy to account for forfeitures as they occur. Sponsorship and Advertising Costs Sponsorship and advertising costs are expensed as incurred. Such expenses for the years ended December 31, 2017 , 2016 , and 2015 totaled $6.6 million , $7.1 million , and $6.4 million , respectively, and are a component of selling, general and administrative expenses on our consolidated statement of earnings. Convertible Senior Notes In September 2014, we issued $250 million principal amount of 1.25% convertible senior notes due 2019 (the “Convertible Notes”) in a private offering. We have separated the Convertible Notes into liability and equity components. The carrying amount of the liability component was determined by measuring the fair value of a similar liability that does not have an associated convertible feature. The carrying value of the equity component representing the conversion option, which is recognized as a debt discount, was determined by deducting the fair value of the liability component from the proceeds of the Convertible Notes. The debt discount is amortized to interest expense using the effective interest method over the term of the Convertible Notes. The equity component will not be remeasured as long as it continues to meet the conditions for equity classification. Refer to Note 7 “Financing Arrangements” for further information regarding the Convertible Notes. Debt Issuance Costs We amortize the costs we incur to obtain debt financing over the contractual life of the related debt using the effective interest method for non-revolving debt and the straight-line method for revolving debt. The amortization expense is included in interest expense, net of interest income in our statement of earnings. Unamortized debt issuance costs attributable to our revolving credit facility are included as a component of other non-current assets. Unamortized debt issuance costs attributable to our Convertible Notes are recorded as a deduction from the carrying amount of the debt liability. Foreign Currency Assets and liabilities of foreign subsidiaries whose functional currency is not the United States Dollar (USD) are translated into the USD using the exchange rates in effect at period end. Revenue and expense items are translated using the average exchange rates for the period. Foreign currency translation adjustments are included in accumulated other comprehensive income, which is a component of stockholders’ equity. Foreign currency transaction gains and losses are included in other income, net on the statement of earnings. We recognized $0.4 million of foreign currency transaction gains in 2017 , de minimis foreign currency transaction gains in 2016 , and $1.6 million of foreign currency transaction losses in 2015 . Segment Reporting Segments are defined as components of a company that engage in business activities from which they may earn revenues and incur expenses, and for which separate financial information is available and is evaluated regularly by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Our chief operating decision maker manages the business under three operating segments, which are reportable segments: Healthcare, Education, and Business Advisory. During the second quarter of 2017, we reorganized our internal financial reporting structure, which management uses to assess performance and allocate resources, by moving our Life Sciences practice from the Education and Life Sciences segment to the Business Advisory segment. The remaining Education and Life Sciences segment is now referred to as the Education segment. While our consolidated results have not been impacted, we have reclassified our historical segment information for consistent presentation. New Accounting Pronouncements Recently Adopted In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . ASU 2018-02 allows entities to reclassify stranded tax effects resulting from the enactment of the 2017 Tax Cuts and Jobs Act ("2017 Tax Reform") from accumulated other comprehensive income to retained earnings. We adopted ASU 2018-02 upon issuance and reclassified $0.5 million of stranded tax effects, primarily related to our convertible debt investment, from accumulated other comprehensive income to retained earnings as of December 31, 2017. Refer to Note 16 "Income Taxes" for additional information on the 2017 Tax Reform. In January 2017, the FASB issued ASU 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . ASU 2017-04 eliminates Step 2 of the goodwill impairment test, which required us to determine the implied fair value of goodwill by allocating the reporting unit's fair value to each of its assets and liabilities as if the reporting unit was acquired in a business acquisition. Instead, the updated guidance requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of the reporting unit to its carrying value, and recognizing a non-cash impairment charge for the amount by which the carrying value exceeds the reporting unit's fair value with the loss not exceeding the total amount of goodwill allocated to that reporting unit. We adopted this ASU in the second quarter of 2017 on a prospective basis and applied the new guidance to our interim goodwill impairment tests performed in the second quarter of 2017 and our annual impairment test performed as of November 30, 2017. Refer to Note 5 “Goodwill and Intangible Assets” for additional information on our interim and annual goodwill impairment tests performed. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting . ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the accounting for income taxes, classification of excess tax benefits on the statement of cash flows, and forfeitures. We adopted this guidance in the first quarter of 2017, at which time we began recognizing excess tax benefits and deficiencies as income tax benefit or expense in our consolidated statements of operations on a prospective basis. We recognized $1.8 million of net excess tax deficiencies as income tax expense in our consolidated statement of operations for the year ended December 31, 2017 . Additionally, upon adoption, we began classifying excess tax benefits as an operating activity on the statement of cash flows on a retrospective basis. As a result, we reclassified $0.9 million and $3.6 million of excess tax benefits for the years ended December 31, 2016 and 2015 , respectively, from cash flows from financing activities to cash flows from operating activities on our statement of cash flows. We elected to account for share-based award forfeitures as they occur, and applied this accounting change on a modified retrospective basis as a cumulative-effect adjustment to retained earnings of $0.4 million during the first quarter of 2017. In March 2016, the FASB issued ASU 2016-06, Derivatives and Hedging: Contingent Put and Call Options in Debt Instruments . ASU 2016-06 clarifies that in assessing whether an embedded contingent put or call option is clearly and closely related to the debt host, an entity is required to perform only the four-step decision sequence in ASC 815-15-25-42 (as amended by the ASU). The entity does not have to separately assess whether the event that triggers its ability to exercise the contingent option is itself indexed only to interest rates or credit risk. We adopted these amendments in the first quarter of 2017 on a modified retrospective basis. The adoption of these amendments did not have any impact on our consolidated financial statements. Not Yet Adopted In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities . The amendments to the guidance improve and simplify accounting rules for hedge accounting to better present the economic results of an entity’s risk management activities in its financial statements and improve the disclosures of hedging arrangements. Additionally, ASU 2017-12 simplifies the hedge documentation and effectiveness assessment requirements. The updated guidance is effective for us beginning January 1, 2019. We do not expect this guidance to have a material impact on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-02, Leases , which supersedes ASC Topic 840, Leases , and sets forth the principles for the recognition, measurement, presentation, and disclosure of leases for both lessees and lessors. ASU 2016-02 requires lessees to classify leases as either finance or operating leases and to record on the balance sheet a right-of-use asset and a lease liability, equal to the present value of the remaining lease payments, for all leases with a term greater than 12 months regardless of the lease classification. The lease classification will determine whether the lease expense is recognized based on an effective interest rate method or a straight-line basis over the term of the lease. ASU 2016-02 will be effective for us beginning January 1, 2019, with early adoption permitted. Entities are required to use a modified retrospective transition method for existing leases. We are currently evaluating the potential impact this guidance will have on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . The amendments to the guidance enhance the reporting model for financial instruments, which includes amendments to address aspects of recognition, measurement, presentation, and disclosure. The updated guidance is effective for us beginning January 1, 2018. We do not expect this guidance to have a material impact on our consolidated financial statements. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, as a new Topic , ASC 606. The new revenue recognition standard provides a five-step analysis of transactions to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In accordance with the new standard, we will adopt ASU 2014-09 on January 1, 2018 using the modified retrospective transition method, under which the new guidance will be applied to the current period presented in the financial statements and a cumulative-effect adjustment will be recorded as of the date of adoption. We are currently completing our analysis to determine the impact of ASC 606 on our consolidated financial statements, and expe

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	Discontinued Operations During 2015, we began evaluating strategic alternatives related to our Huron Legal segment, including the potential divestiture of the practice. On December 10, 2015, we entered into an agreement to sell Huron Legal to Consilio, Inc. ("Consilio"). Pursuant to this agreement, Consilio acquired substantially all of the assets and assumed certain liabilities of Huron Legal, and acquired all issued and outstanding equity interests in certain entities wholly owned by Huron. Huron Legal provided eDiscovery services, consulting services and contract management services related to law department management, information governance and compliance, legal discovery, litigation management, and legal analytics. The sale closed on December 31, 2015, at which time we received proceeds of $110.1 million and recognized a pretax disposal loss of $2.3 million . The divestiture of the Huron Legal segment represented a strategic shift that had a major effect on our operations and financial results. As such, the operations of our Huron Legal segment have been classified as discontinued operations in our consolidated statements of operations for all periods presented. As of December 31, 2017 and 2016 , no assets or liabilities of the disposed business remained on our consolidated balance sheets. For the year ended December 31, 2017 , we recognized income from discontinued operations, net of tax, of $0.4 million primarily related to updated lease assumptions for vacated office space directly related to the sale of the Huron Legal segment. For the year ended December 31, 2016 , we recognized a loss from discontinued operations, net of tax, of $1.9 million , primarily related to obligations for former employees, legal fees, and updated lease assumptions for vacated office space directly related to the sale of the Huron Legal segment. The table below summarizes the operating results of Huron Legal for the year ended December 31, 2015. Year Ended Revenues and reimbursable expenses: Revenues $ 139,430 Reimbursable expenses 3,148 Total revenues and reimbursable expenses 142,578 Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses): Direct costs 95,247 Amortization of intangible assets and software development costs 233 Reimbursable expenses 3,153 Total direct costs and reimbursable expenses 98,633 Operating expenses and other operating gain: Selling, general and administrative expenses 20,640 Restructuring charges (1) 13,341 Other gain (900 ) Depreciation and amortization 9,605 Total operating expenses and other operating gain 42,686 Operating income 1,259 Other expense, net (13 ) Income from discontinued operations before taxes 1,246 Loss on disposal (2,303 ) Total loss from discontinued operations before taxes (1,057 ) Income tax benefit (2) 1,786 Net loss from discontinued operations $ (2,843 ) (1) During 2015, the Huron Legal segment incurred a $13.3 million restructuring charge. Of the $13.3 million , $6.1 million related to accelerated depreciation on assets disposed of as a result of the sale, $5.1 million related to employee costs incurred in connection with the sale, $1.1 million related to the accrual of our remaining lease obligations for vacated spaces, net of estimated sublease income, and $1.0 million related to severance costs incurred from prior workforce reductions. (2) Refer to Note 16 "Income Taxes" for additional detail on the income tax benefit recognized for discontinued operations. The table below summarizes the amounts reflected in our consolidated statements of cash flows that relate to the discontinued operations for the year ended December 31, 2015. Year Ended Depreciation and amortization $ 15,974 Share-based compensation $ 2,215 Purchases of property and equipment $ 6,234 Significant non-cash investing items of discontinued operations: Contingent consideration related to a business acquisition $ 900 In connection with the sale of Huron Legal, we entered into a transition services agreement ("TSA") with Consilio, under which we provided certain post-closing services, support, and facilities to Consilio to facilitate an orderly transfer of the Huron Legal business operations. Billings under the TSA, which we did not consider to be significant, were recorded as a reduction of the costs to provide the respective services, primarily in selling, general and administrative expenses in the consolidated statements of operations. Services under the TSA ended as of June 30, 2017. We have no continuing involvement with the Huron Legal segment.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions	Acquisitions 2017 Pope Woodhead and Associates Limited On January 9, 2017, we completed our acquisition of Pope Woodhead and Associates Limited ("Pope Woodhead"), a U.K.-based consulting firm providing market access capabilities to assist clients in developing value propositions for innovative medicines and technologies. The acquisition expands our life sciences strategy expertise and strengthens our ability to lead clients through complex payer and regulatory environments. Pope Woodhead's results of operations have been included in our consolidated financial statements and the results of operations of our Business Advisory segment from the date of acquisition. ADI Strategies, Inc. On April 1, 2017, we completed our acquisition of the international assets of ADI Strategies, Inc. ("ADI Strategies") in Dubai and India. We acquired the U.S. assets of ADI Strategies in the second quarter of 2016. ADI Strategies is a leading enterprise performance management, risk management and business intelligence firm. The acquisition strengthens our technology and analytics competencies and expands our global reach. The international results of operations of ADI Strategies have been included in our consolidated financial statements and results of operations of the Business Advisory segment from the date of acquisition. The acquisitions of ADI Strategies and Pope Woodhead are not significant to our consolidated financial statements individually or in the aggregate as of and for the twelve months ended December 31, 2017. Innosight Holdings, LLC On March 1, 2017 , we acquired 100% of the membership interests of Innosight Holdings, LLC ("Innosight"). Innosight is a growth strategy firm focused on helping companies navigate disruptive change and manage strategic transformation. Together with Innosight, we use our strategic, operational, and technology capabilities to help clients across multiple industries develop pioneering solutions to address disruption and achieve sustained growth. The acquisition was accounted for using the acquisition method of accounting. Tangible and identifiable intangible assets acquired and liabilities assumed are recorded at fair value as of the acquisition date. The current fair values of assets acquired and liabilities assumed are considered preliminary and are based on the information that is currently available. We believe that the information provides a reasonable basis for estimating the preliminary fair values of assets acquired and liabilities assumed, but certain items, such as working capital amounts, may be subject to change as additional information is received. Thus, the provisional measurements of fair value and goodwill are subject to change. We will finalize the valuation in the first quarter of 2018. The acquisition date fair value of the consideration transferred for Innosight was $113.6 million , which consisted of the following: Fair value of consideration transferred Cash $ 90,725 Common stock 9,560 Contingent consideration liability 12,050 Net working capital adjustment 1,272 Total consideration transferred $ 113,607 We funded the cash component of the purchase price with cash on hand and borrowings of $89.0 million under our senior secured credit facility. We issued 221,558 shares of our common stock as part of the consideration transferred, with an acquisition date fair value of $9.6 million based on our common stock's closing price of $43.15 on the date of acquisition. The contingent consideration liability of $12.1 million represents the acquisition date fair value of the contingent consideration arrangement, pursuant to which we may be required to pay additional consideration to the sellers if specific financial performance targets are met over a four-year term. The maximum amount of contingent consideration that may be paid is $35.0 million . See Note 12 "Fair Value of Financial Instruments" for additional information on the valuation of contingent consideration liabilities. The following table summarizes the preliminary allocation of the purchase price to the fair value of assets acquired and liabilities assumed as of the acquisition date. March 1, 2017 Assets acquired: Accounts receivable $ 7,752 Unbilled services 1,881 Prepaid expenses and other current assets 468 Property and equipment 419 Intangible assets 18,015 Liabilities assumed: Accounts payable 531 Accrued expenses and other current liabilities 894 Accrued payroll and related benefits 883 Deferred revenues 30 Total identifiable net assets 26,197 Goodwill 87,410 Total purchase price $ 113,607 The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the acquisition date. Fair Value Useful Life in Years Customer relationships $ 9,500 6 Trade name 6,000 6 Customer contracts 1,000 1 Non-compete agreements 1,300 5 Favorable lease contract 215 1 Total intangible assets subject to amortization $ 18,015 The weighted average amortization period for the identifiable intangible assets shown above is 5.6 years. Customer relationships and customer contracts represent the fair values of the underlying relationships and agreements with Innosight customers. The trade name represents the fair value of the brand and name recognition associated with the marketing of Innosight's service offerings. Non-compete agreements represent the value derived from preventing certain Innosight executives from entering into or starting a similar, competing business. The favorable lease contract represents the difference between the fair value and minimum lease obligations under the current outstanding lease. Goodwill is recognized for the excess of purchase price over the net fair value of assets acquired and liabilities assumed, and largely reflects the expanded market opportunities expected from combining the service offerings of Huron and Innosight, as well as the assembled workforce of Innosight. Goodwill recognized in conjunction with the acquisition of Innosight was recorded in the Business Advisory segment. Goodwill of $87.4 million is expected to be deductible for income tax purposes. Innosight’s results of operations have been included in our unaudited consolidated statements of operations and results of operations of our Business Advisory segment from the date of acquisition. For the year ended December 31, 2017 , revenues from Innosight were $34.3 million and operating loss was $0.9 million , which included $3.4 million of amortization expense for intangible assets acquired. In connection with the acquisition of Innosight, we incurred $1.7 million of transaction and acquisition-related expenses. Of the $1.7 million of expense, $1.4 million was incurred in the first quarter of 2017 and $0.3 million was incurred in the second quarter in 2017. These costs are recorded in selling, general and administrative expenses. The following unaudited supplemental pro forma information summarizes the combined results of operations of Huron and Innosight as though the companies were combined on January 1, 2016. Year Ended December 31, 2017 2016 Revenues $ 741,695 $ 769,114 Net income (loss) from continuing operations $ (167,346 ) $ 42,760 Net income (loss) from continuing operations per share - basic $ (7.79 ) $ 2.01 Net income (loss) from continuing operations per share - diluted $ (7.79 ) $ 1.98 The historical financial information has been adjusted to give effect to pro forma adjustments consisting of intangible asset amortization expense, acquisition-related costs, interest expense, and the related income tax effects. The unaudited pro forma information above includes adjustments to include additional expense of $0.6 million and $11.4 million for the years ended December 31, 2017 and 2016 , respectively. Additionally, the historical financial information has been adjusted to give effect to the shares issued as consideration. All of these adjustments are based upon currently available information and certain assumptions. Therefore, the pro forma consolidated results are not necessarily indicative of what our consolidated results of operations actually would have been had we completed the acquisition on January 1, 2016. The historical results included in the pro forma consolidated results do not purport to project future results of operations of the combined companies nor do they reflect the expected realization of any cost savings or revenue synergies associated with the acquisition. 2016 MyRounding Solutions, LLC On February 1, 2016, we completed the acquisition of MyRounding Solutions, LLC ("MyRounding"), a Denver, Colorado-based firm specializing in digital health solutions to improve patient care. The MyRounding application is designed to standardize, automate, and track rounding activity, allowing nurses and staff to improve the care and experience of patients in real time. The addition of MyRounding expands the integration of our software and consulting solutions and strengthens our transformation services for healthcare providers. The results of operations of MyRounding have been included in our consolidated financial statements and the results of operations of our Healthcare segment from the date of acquisition. ADI Strategies, Inc. On May 1, 2016, we completed the acquisition of the U.S. assets of ADI Strategies, Inc. ("ADI Strategies"), a leading enterprise performance management, risk management, and business intelligence firm focused on implementing the Oracle enterprise application suite. The results of operations of ADI Strategies have been included in our consolidated financial statements and the results of operations of our Business Advisory segment from the date of acquisition. Healthcare Services Management, Inc. On August 1, 2016, we completed the acquisition of Healthcare Services Management, Inc. ("HSM Consulting"), a firm specializing in healthcare information technology and management consulting. The results of operations of HSM Consulting have been included in our consolidated financial statements and results of operations of our Healthcare segment from the date of acquisition. The acquisitions of MyRounding, ADI Strategies, and HSM Consulting are not significant to our consolidated financial statements individually or in the aggregate as of and for the twelve months ended December 31, 2016. 2015 Studer Holdings, Inc. On February 12, 2015 , we acquired 100% of the outstanding stock of Studer Holdings, Inc. (“Studer Group”) from the existing shareholders in accordance with an Agreement and Plan of Merger dated January 26, 2015 (the “Merger Agreement”). Studer Group is a professional services firm that assists healthcare providers achieve cultural transformation to deliver and sustain improvement in clinical outcomes and financial results. The acquisition combines Healthcare’s performance improvement and clinical transformation capabilities with Studer Group’s Evidence-Based Leadership SM framework to provide leadership and cultural transformation expertise for healthcare provider clients. The acquisition date fair value of the consideration transferred for Studer Group was approximately $325.2 million , which consisted of the following: Fair value of consideration transferred Cash $ 323,237 Common stock 2,204 Net working capital adjustment (255 ) Total consideration transferred $ 325,186 We funded the cash component of the purchase price with cash on hand and borrowings of $102.0 million under our senior secured credit facility. We issued 28,486 shares of our common stock as part of the consideration transferred, with an acquisition date fair value of $2.2 million based on the closing price of our stock of $77.35 on the date of acquisition. The acquisition was accounted for using the acquisition method of accounting. Tangible and identifiable intangible assets acquired and liabilities assumed are recorded at fair value as of the acquisition date. The following table summarizes the allocation of the purchase price to the fair value of assets acquired and liabilities assumed as of the acquisition date. February 12, 2015 Assets acquired: Accounts receivable $ 14,906 Prepaid expenses and other current assets 1,385 Deferred income tax asset 4,335 Property and equipment 4,509 Intangible assets 97,500 Liabilities assumed: Accounts payable 760 Accrued expenses and other current liabilities 2,868 Accrued payroll and related benefits 1,574 Deferred revenues 2,449 Deferred income tax liability 21,263 Other non-current liabilities 1,211 Total identifiable net assets 92,510 Goodwill 232,676 Total purchase price $ 325,186 The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the acquisition date. Fair Value Useful Life in Years Customer relationships $ 42,400 9 Customer contracts 25,100 4 Trade name 22,800 5 Technology and software 3,900 3 Publishing content 3,300 3 Total intangible assets subject to amortization $ 97,500 The weighted average amortization period for the identifiable intangible assets shown above is 6.3 years. Customer relationships and customer contracts represent the fair values of the underlying relationships and agreements with Studer Group customers. The trade name represents the fair value of the brand and name recognition associated with the marketing of Studer Group’s service offerings. Technology and software and publishing content represent the estimated fair values of Studer Group’s software and books that are sold to customers. Goodwill is recognized for the excess of purchase price over the net fair value of assets acquired and liabilities assumed, and largely reflects the expanded market opportunities expected from combining the service offerings of Huron and Studer Group, as well as the assembled workforce of Studer Group. Goodwill recognized in conjunction with the acquisition of Studer Group was recorded in the Healthcare segment. Goodwill of $119.5 million is expected to be deductible for income tax purposes. Studer Group’s results of operations have been included in our consolidated statements of operations and other comprehensive income and results of operations of our Healthcare segment from the date of acquisition. For the year ended December 31, 2015, revenues from Studer Group were $79.9 million and operating income was $5.1 million , which included $21.3 million of amortization expense for intangible assets acquired. In connection with the acquisition of Studer Group, we incurred $2.1 million of transaction and acquisition-related expenses, $0.9 million of which were incurred in 2014, and $1.2 million of which were incurred in 2015. These costs are recorded in selling, general and administrative expenses in the period in which they were incurred. The following unaudited supplemental pro forma information summarizes the combined results of operations for Huron and Studer Group for the twelve months ended December 31, 2015 as though the companies were combined on January 1, 2014. Year Ended December 31, 2015 Revenues $ 709,813 Net income from continuing operations $ 63,600 Net income from continuing operations per share - basic $ 2.87 Net income from continuing operations per share - diluted $ 2.81 The historical financial information shown above has been adjusted to give effect to pro forma adjustments totaling $2.4 million of additional expense, which consist of intangible assets amortization expense, acquisition-related costs, interest expense, and the related income tax effects. The historical per share information has been adjusted to give effect to the shares issued as consideration. These adjustments are based upon currently available information and certain assumptions. Therefore, the pro forma consolidated results are not necessarily indicative of what our consolidated results of operations actually would have been had we completed the acquisition on January 1, 2014. The historical results included in the pro forma consolidated results do not purport to project future results of operations of the combined companies, nor do they reflect the expected realization of any cost savings or revenue synergies associated with the acquisition. Sky Analytics, Inc. Effective January 1, 2015, we completed the acquisition of Sky Analytics, Inc. ("Sky Analytics"), a Massachusetts-based provider of legal spend management software for corporate law departments. Sky Analytics' results of operations were included in the results of operations of our Huron Legal segment from the date of acquisition, and classified as discontinued operations upon the sale of the Huron Legal segment in the fourth quarter of 2015. Refer to Note 3 "Discontinued Operations" for additional detail on the sale of the Huron Legal segment. Rittman Mead India Effective July 1, 2015, we completed the acquisition of Rittman Mead Consulting Private Limited ("Rittman Mead India"), the India affiliate of Rittman Mead Consulting Ltd. Rittman Mead India is a data and analytics consulting firm that specializes in the implementation of enterprise performance management and analytics systems. Rittman Mead India's results of operations have been included in our consolidated financial statements and results of operations of our Business Advisory segment from the date of acquisition. Cloud62, Inc. Effective October 1, 2015, we completed the acquisition of Cloud62, Inc. ("Cloud62"), a New York-based consulting firm specializing in Salesforce.com implementations and related cloud-based applications. Cloud62's results of operations have been included in our consolidated financial statements and results of operations of our Business Advisory segment from the date of acquisition. The acquisitions of Sky Analytics, Rittman Mead India, and Cloud62 were not significant to our consolidated financial statements individually or in the aggregate as of and for the twelve months ended December 31, 2015.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets The table below sets forth the changes in the carrying amount of goodwill by reportable segment for the years ended December 31, 2017 and 2016 . Healthcare Education Business Advisory Total Balance as of December 31, 2015: Goodwill $ 610,264 $ 102,906 $ 181,213 $ 894,383 Accumulated impairment losses — — (142,983 ) (142,983 ) Goodwill, net as of December 31, 2015 $ 610,264 $ 102,906 $ 38,230 $ 751,400 Goodwill recorded in connection with business combinations (1) 26,538 — 21,824 48,362 Foreign currency translation — — 100 100 Balance as of December 31, 2016: Goodwill 636,802 102,906 203,137 942,845 Accumulated impairment losses — — (142,983 ) (142,983 ) Goodwill, net as of December 31, 2016 $ 636,802 $ 102,906 $ 60,154 $ 799,862 Goodwill recorded in connection with business combinations (1) 8 10,252 88,183 98,443 Goodwill impairment charge (208,081 ) — (45,012 ) (253,093 ) Goodwill reallocation (2) — (10,794 ) 10,794 — Goodwill allocated to disposal of business (3) — — (568 ) (568 ) Foreign currency translation — 465 641 1,106 Balance as of December 31, 2017: Goodwill 636,810 102,829 302,187 1,041,826 Accumulated impairment losses (208,081 ) — (187,995 ) (396,076 ) Goodwill, net as of December 31, 2017: $ 428,729 $ 102,829 $ 114,192 $ 645,750 (1) Refer to Note 4 "Acquisitions" for additional information on the goodwill recorded in connection with business combinations. (2) In the second quarter of 2017, we reorganized our internal financial reporting structure, which management uses to assess performance and allocate resources, by moving our Life Sciences practice from the Education and Life Sciences segment to the Business Advisory segment. The remaining Education and Life Sciences segment is now referred to as the Education segment. The Life Sciences practice is a separate reporting unit for purposes of goodwill impairment testing. See Note 18 "Segment Information" for additional information on our reportable segments. (3) On June 16, 2017, we sold our Life Sciences Compliance and Operations practice ("Life Sciences C&O") to a third-party, and allocated a portion of goodwill within the Life Sciences reporting unit to the disposed business based on the relative fair values of Life Sciences C&O and the remaining reporting unit. The allocated goodwill of $0.6 million was written off and included in the gain on sale of Life Sciences C&O. The sale of Life Sciences C&O did not meet the criteria for reporting separately as discontinued operations. In connection with the sale, we recorded a $0.9 million gain which is included in other income, net in our consolidated statements of operations. Second Quarter 2017 Goodwill Impairment Charge During the second quarter of 2017, we performed a goodwill impairment analysis for our Healthcare reporting unit as our Healthcare business had experienced a prolonged period of declining revenues, primarily driven by softness in our revenue cycle offering within our performance improvement solution. This softness was attributable to decreased demand for our services, the winding down of some of our larger projects, and a trend toward smaller projects, as well as fewer large integrated projects. In light of these challenges, several initiatives were undertaken to improve the segment's financial performance, including repositioning our solutions to address the most critical needs of our clients, the expansion of our existing services such as those in our Studer Group, strategy, physician and technology offerings, and workforce reductions to better align resources with market demand. While these initiatives have yielded some positive impacts, hospitals and health systems continue to face regulatory and funding uncertainty; therefore, we remain cautious about near-term growth. As we had previously disclosed in prior quarters, if the financial performance of our Healthcare segment continued to decline and did not meet our expectations, we could be required to perform an interim impairment analysis with respect to our carrying value of goodwill for the Healthcare reporting unit prior to our usual annual test. Based on forecasts prepared in the second quarter of 2017 in connection with our quarterly forecasting cycle, we determined that the likely time frame to improve the financial results of this segment would take longer than originally anticipated. As such, we concluded, during the second quarter of 2017, that the fair value of the Healthcare reporting unit may have no longer exceeded its carrying value. In connection with the preparation of our financial statements for the quarter ended June 30, 2017, we performed an interim impairment test on the Healthcare reporting unit. Our goodwill impairment test was performed by comparing the fair value of the Healthcare reporting unit with its carrying value and, in accordance with ASU 2017-04, which we adopted in the second quarter of 2017, recognizing an impairment charge for the amount by which the carrying value exceeded the fair value. To estimate the fair value of the Healthcare reporting unit, we relied on a combination of the income approach and the market approach, utilizing the guideline company method, with a fifty-fifty weighting. Based on the estimated fair value of the Healthcare reporting unit, we recorded a $209.6 million non-cash pretax charge in the second quarter of 2017 to reduce the carrying value of goodwill in our Healthcare reporting unit. As discussed in Note 2 "Summary of Significant Accounting," during the fourth quarter of 2017, we identified that our calculation of the non-deductible portion of our goodwill impairment charge recorded in the second quarter of 2017 erroneously excluded a portion of goodwill that was related to an acquisition completed in 2008 and has since been divested. To correct this error, in the fourth quarter of 2017, we recorded a $1.5 million decrease to our non-cash pretax goodwill impairment charge related to our Healthcare reporting unit. The total non-cash pretax goodwill impairment charge recorded in 2017 related to our Healthcare reporting unit, including the adjustment in the fourth quarter of 2017, was $208.1 million . In connection with the goodwill impairment test performed on the Healthcare reporting unit, we performed an impairment test on the long-lived assets allocated to the asset groups within the Healthcare reporting unit. Based on the impairment test performed, we concluded that the long-lived assets allocated to the asset groups within the Healthcare reporting unit were not impaired as of June 30, 2017. Second Quarter 2017 Goodwill Reallocation As a result of the segment reorganization in the second quarter of 2017, we reallocated $10.8 million of the goodwill balance associated with the previous Education and Life Sciences reporting unit to the new Life Sciences reporting unit based on the relative fair values of the Life Sciences reporting unit and the remaining Education reporting unit. The estimated fair values were determined using a combination of the income approach and the market approach, utilizing the guideline company method, with a fifty-fifty weighting. In conjunction with the goodwill reallocation, we performed a goodwill impairment test for the goodwill balances within our Education reporting unit and Life Sciences reporting unit as of June 1, 2017. Based on the results of the goodwill impairment test, we determined that the fair values of our Education reporting unit and Life Sciences reporting unit exceeded their carrying values. As such, we concluded that there was no indication of goodwill impairment for either reporting unit at that time. 2017 Annual Goodwill Impairment Test Pursuant to our policy, we performed our annual goodwill impairment test as of November 30, 2017 for our six reporting units with goodwill balances: Healthcare, Education, Business Advisory, Enterprise Solutions and Analytics, Strategy and Innovation, and Life Sciences. We elected to bypass the qualitative assessment and proceeded directly to the quantitative goodwill impairment test. For each reporting unit, we reviewed goodwill for impairment by comparing the fair value of the reporting unit to its carrying value, including goodwill. In estimating the fair value of each reporting unit, we relied on a combination of the income approach and the market approach, utilizing the guideline company method, with a fifty-fifty weighting. Based on the results of the goodwill impairment test, we determined that the fair value of the Healthcare, Education, Business Advisory, Strategy and Innovation, and Life Sciences reporting units exceeded its carrying value by 40% , 120% , 115% , 33% , and 14% , respectively. As such, we concluded that there was no indication of goodwill impairment for these five reporting units. However, the results of the quantitative impairment test indicated that the fair value of the Enterprise Solutions and Analytics reporting unit did not exceed its carrying value. Based on the estimated fair value of the Enterprise Solutions and Analytics reporting unit, we recorded a $45.0 million non-cash pretax charge to reduce the carrying value of this reporting unit's goodwill to zero. Our Enterprise Solutions and Analytics reporting unit was established with the acquisition of Blue Stone International, LLC in 2013. Since that time, we completed five additional business acquisitions within the reporting unit, most recently the acquisitions of the U.S. assets and international assets of ADI Strategies in May 2016 and April 2017, respectively. We record the assets acquired and liabilities assumed in business combinations, including identifiable intangible assets, at their estimated fair values as of the acquisition date, and goodwill is recorded as the excess of the fair value of consideration transferred, including any contingent consideration, over the fair value of the net assets acquired. Therefore, the initial accounting for an acquisition results in its fair value equaling its carrying value. As we have previously disclosed in prior quarters, due to this reporting unit’s relatively low headroom, in the event that the financial performance of the reporting unit did not meet our expectations during 2017, we could be required to take a non-cash impairment charge as a result of any goodwill impairment test. During the first three quarters of 2017, the performance of Enterprise Solutions and Analytics continued to reasonably meet our expectations. However, both revenues and operating margin during the fourth quarter of 2017 fell short of our expectations resulting in a reduction in workforce within the reporting unit during that quarter. Further, in connection with our annual budget process for 2018, which coincided with our annual goodwill impairment test during the fourth quarter of 2017, we determined that the reporting unit's expected future revenue growth rates and operating margin would be lower than previously anticipated for this reporting unit. As a result, our goodwill impairment test indicated that the fair value of the Enterprise Solutions and Analytics reporting unit no longer exceeded its carrying value, and we recorded a $45.0 million non-cash pretax charge to write off the entire carrying value of this reporting unit's goodwill. In connection with the goodwill impairment test performed on the Enterprise Solutions and Analytics reporting unit, we performed an impairment test on the long-lived assets allocated to the asset groups within the Enterprise Solutions and Analytics reporting unit. Based on the impairment test performed, we concluded that the long-lived assets allocated to the asset groups within the Enterprise Solutions and Analytics reporting unit were not impaired as of November 30, 2017. Further, we evaluated whether any events have occurred or any circumstances have changed since November 30, 2017 that would indicate any additional goodwill may have become impaired since our annual impairment test. Based on our evaluation as of December 31, 2017 , which included the impact of the 2017 Tax Reform on our deferred tax balances and forecasted tax rates, we determined that no indications of impairment have arisen since our annual goodwill impairment test. The results of an impairment analysis are as of a point in time. There is no assurance that the actual future earnings or cash flows of our reporting units will be consistent with our projections. We will monitor any changes to our assumptions and will evaluate goodwill as deemed warranted during future periods. Any significant decline in our operations could result in additional non-cash goodwill impairment charges. Intangible Assets Intangible assets as of December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Useful Life in Years Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer relationships 4 to 13 $ 106,195 $ 51,588 $ 89,279 $ 34,827 Trade names 2 to 6 29,016 18,915 22,930 11,652 Customer contracts 1 to 4 25,154 24,751 26,497 21,295 Technology and software 3 to 5 9,340 5,098 8,970 2,667 Non-competition agreements 3 to 5 5,163 2,637 3,685 1,697 Publishing content 3 3,300 3,163 3,300 2,062 Favorable lease contract 3 720 425 720 203 In-process technology Indefinite — — 370 — Total $ 178,888 $ 106,577 $ 155,751 $ 74,403 Identifiable intangible assets with finite lives are amortized over their estimated useful lives. Customer relationships and customer contracts, as well as certain trade names and technology and software, are amortized on an accelerated basis to correspond to the cash flows expected to be derived from the assets. All other intangible assets with finite lives are amortized on a straight-line basis. In connection with the acquisition of MyRounding, we acquired in-process technology which was accounted for as an indefinite-lived intangible asset until the development of the technology was complete, which occurred in the first quarter of 2017. Upon completion, we reclassified the technology to definite-lived technology and software, and began amortizing the asset over a five -year useful life on a straight-line basis. Intangible assets amortization expense was $35.0 million , $33.1 million , and $28.7 million for the years ended December 31, 2017 , 2016 , and 2015 , respectively. The table below sets forth the estimated annual amortization expense for each of the five succeeding years for the intangible assets recorded as of December 31, 2017 . Year Ending December 31, Estimated Amortization Expense 2018 $ 23,936 2019 $ 17,279 2020 $ 12,116 2021 $ 8,070 2022 $ 6,092 Actual future amortization expense could differ from these estimated amounts as a result of future acquisitions, dispositions, and other factors.

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Depreciation expense for property and equipment was $13.3 million , $12.5 million , and $12.3 million for the years ended December 31, 2017 , 2016 , and 2015 , respectively. Property and equipment, net at December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Computers, related equipment, and software $ 46,216 $ 48,607 Leasehold improvements 45,244 38,502 Furniture and fixtures 16,434 12,545 Aircraft 7,541 — Assets under construction 250 294 Property and equipment 115,685 99,948 Accumulated depreciation and amortization (70,144 ) (67,514 ) Property and equipment, net $ 45,541 $ 32,434

Financing Arrangements

Financing Arrangements	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Financing Arrangements	Financing Arrangements A summary of the carrying amounts of our debt follows: As of December 31, 2017 2016 1.25% convertible senior notes due 2019 $ 233,140 $ 224,065 Senior secured credit facility 105,000 68,000 Promissory note due 2024 4,868 — Total long-term debt $ 343,008 $ 292,065 Current maturities of debt (1) (501 ) — Long-term debt, net of current portion $ 342,507 $ 292,065 (1) The current maturities of debt are included as a component of accrued expenses and other current liabilities on our consolidated balance sheets. Below is a summary of the scheduled remaining principal payments of our debt as of December 31, 2017 . Principal Payments of Long-Term Debt 2018 $ 501 2019 $ 250,515 2020 $ 105,529 2021 $ 544 2022 $ 559 Thereafter $ 2,221 Convertible Notes In September 2014, the Company issued $250 million principal amount of 1.25% convertible senior notes due 2019 (the “Convertible Notes”) in a private offering. The Convertible Notes are governed by the terms of an indenture between the Company and U.S. Bank National Association, as Trustee (the “Indenture”). The Convertible Notes are senior unsecured obligations of the Company and will pay interest semi-annually on April 1 and October 1 of each year at an annual rate of 1.25% . The Convertible Notes will mature on October 1, 2019 , unless earlier repurchased by the Company or converted in accordance with their terms. Upon conversion, the Convertible Notes will be settled, at our election, in cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock. Our current intent and policy is to settle conversions with a combination of cash and shares of common stock with the principal amount of the Convertible Notes paid in cash, in accordance with the settlement provisions of the Indenture. The initial conversion rate for the Convertible Notes is 12.5170 shares of our common stock per $1,000 principal amount of the Convertible Notes, which is equal to an initial conversion price of approximately $79.89 per share of our common stock. The conversion rate will be subject to adjustment upon the occurrence of certain specified events but will not be adjusted for accrued and unpaid interest, except in certain limited circumstances described in the Indenture. Upon the occurrence of a “make-whole fundamental change” (as defined in the Indenture) the Company will, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its Convertible Notes in connection with such make-whole fundamental change. Additionally, if the Company undergoes a “fundamental change” (as defined in the Indenture), a holder will have the option to require the Company to repurchase all or a portion of its Convertible Notes for cash at a price equal to 100% of the principal amount of the Convertible Notes being repurchased plus any accrued and unpaid interest. As discussed below, the convertible note hedge transactions and warrants, which were entered into in connection with the Convertible Notes, effectively raise the price at which economic dilution would occur from the initial conversion price of approximately $79.89 to approximately $97.12 per share. Holders of the Convertible Notes may convert their Convertible Notes at their option at any time prior to July 1, 2019 , only under the following circumstances: • during any calendar quarter (and only during such calendar quarter) commencing after December 31, 2014 if, for each of at least 20 trading days (whether or not consecutive) during the 30 consecutive trading day period ending on, and including, the last trading day of the immediately preceding calendar quarter, the last reported sale price of the Company’s common stock for such trading day is equal to or greater than 130% of the applicable conversion price on such trading day; • during the five consecutive business day period immediately following any five consecutive trading day period (such five consecutive trading day period, the “measurement period”) in which, for each trading day of the measurement period, the “trading price” (as defined in the Indenture) per $1,000 principal amount of the Convertible Notes for such trading day was less than 98% of the product of the last reported sale price of the Company’s common stock for such trading day and the applicable conversion rate on such trading day; or • upon the occurrence of specified corporate transactions described in the Indenture. On or after July 1, 2019 until the close of business on the second scheduled trading day immediately preceding the maturity date, a holder may convert all or a portion of its Convertible Notes, regardless of the foregoing circumstances. We have separated the Convertible Notes into liability and equity components. The carrying amount of the liability component was determined by measuring the fair value of a similar liability that does not have an associated convertible feature, assuming our non-convertible debt borrowing rate. The carrying value of the equity component representing the conversion option, which is recognized as a debt discount, was determined by deducting the fair value of the liability component from the proceeds of the Convertible Notes. The debt discount is amortized to interest expense using an effective interest rate of 4.751% over the term of the Convertible Notes. As of December 31, 2017 , the remaining life of the Convertible Notes is 1.8 years. The equity component will not be remeasured as long as it continues to meet the conditions for equity classification. The transaction costs related to the issuance of the Convertible Notes were separated into liability and equity components based on their relative values, as determined above. Transaction costs attributable to the liability component are recorded as a deduction to the carrying amount of the liability and amortized to interest expense over the term of the Convertible Notes; and transaction costs attributable to the equity component are netted with the equity component of the Convertible Notes in stockholders’ equity. Total debt issuance costs were approximately $7.3 million , of which $6.2 million was allocated to liability issuance costs and $1.1 million was allocated to equity issuance costs. As of December 31, 2017 and 2016 , the Convertible Notes consisted of the following: As of December 31, 2017 2016 Liability component: Proceeds $ 250,000 $ 250,000 Less: debt discount, net of amortization (14,668 ) (22,520 ) Less: debt issuance costs, net of amortization (2,192 ) (3,415 ) Net carrying amount $ 233,140 $ 224,065 Equity component (1) $ 39,287 $ 39,287 (1) Included in additional paid-in capital on the consolidated balance sheet. The following table presents the amount of interest expense recognized related to the Convertible Notes for the periods presented. Year Ended December 31, 2017 2016 2015 Contractual interest coupon $ 3,125 $ 3,125 $ 3,125 Amortization of debt discount 7,851 7,488 7,141 Amortization of debt issuance costs 1,224 1,201 1,180 Total interest expense $ 12,200 $ 11,814 $ 11,446 In connection with the issuance of the Convertible Notes, we entered into convertible note hedge transactions and warrant transactions. The convertible note hedge transactions are intended to reduce the potential future economic dilution associated with the conversion of the Convertible Notes and, combined with the warrants, effectively raise the price at which economic dilution would occur from the initial conversion price of approximately $79.89 to approximately $97.12 per share. For purposes of the computation of diluted earnings per share in accordance with GAAP, dilution will occur when the average share price of our common stock for a given period exceeds the conversion price of the Convertible Notes, which initially is equal to approximately $79.89 per share. The convertible note hedge transactions and warrant transactions are discussed separately below. • Convertible Note Hedge Transactions . In connection with the issuance of the Convertible Notes, the Company entered into convertible note hedge transactions whereby the Company has call options to purchase a total of approximately 3.1 million shares of the Company’s common stock, which is the number of shares initially issuable upon conversion of the Convertible Notes in full, at a price of approximately $79.89 , which corresponds to the initial conversion price of the Convertible Notes, subject to customary anti-dilution adjustments substantially similar to those in the Convertible Notes. The convertible note hedge transactions are exercisable upon conversion of the Convertible Notes and will expire in 2019 if not earlier exercised. We paid an aggregate amount of $42.1 million for the convertible note hedge transactions, which was recorded as additional paid-in capital on the consolidated balance sheets. The convertible note hedge transactions are separate transactions and are not part of the terms of the Convertible Notes. • Warrants. In connection with the issuance of the Convertible Notes, the Company sold warrants whereby the holders of the warrants have the option to purchase a total of approximately 3.1 million shares of the Company’s common stock at a strike price of approximately $97.12 . The warrants will expire incrementally on 100 different dates from January 6, 2020 to May 28, 2020 and are exercisable at each such expiry date. If the average market value per share of our common stock for the reporting period exceeds the strike price of the warrants, the warrants will have a dilutive effect on our earnings per share. We received aggregate proceeds of $23.6 million from the sale of the warrants, which was recorded as additional paid-in capital on the consolidated balance sheets. The warrants are separate transactions and are not part of the terms of the Convertible Notes or the convertible note hedge transactions. The Company recorded an initial deferred tax liability of $15.4 million in connection with the debt discount associated with the Convertible Notes and recorded an initial deferred tax asset of $16.5 million in connection with the convertible note hedge transactions. The deferred tax liability and deferred tax asset are included in deferred income taxes, net on the consolidated balance sheets. Senior Secured Credit Facility The Company has a $500 million five -year senior secured revolving credit facility, subject to the terms of a Second Amended and Restated Credit Agreement dated as of March 31, 2015, as amended to date (as amended and modified the "Amended Credit Facility"), that becomes due and payable in full upon maturity on March 31, 2020 . The Amended Credit Agreement provides the option to increase the revolving credit facility or establish term loan facilities in an aggregate amount of up to $100 million , subject to customary conditions and the approval of any lender whose commitment would be increased, resulting in a maximum available principal amount under the Amended Credit Agreement of $600 million . The initial borrowings under the Amended Credit Agreement were used to refinance borrowings outstanding under a prior credit agreement, and future borrowings under the Amended Credit Agreement may be used for working capital, capital expenditures, acquisitions of businesses, share repurchases, and general corporate purposes. Fees and interest on borrowings vary based on our Consolidated Leverage Ratio (as defined in the Amended Credit Agreement). At our option, borrowings under the Amended Credit Agreement will bear interest at one, two, three or six-month LIBOR or an alternate base rate, in each case plus the applicable margin. The applicable margin will fluctuate between 1.25% per annum and 2.00% per annum, in the case of LIBOR borrowings, or between 0.25% per annum and 1.00% per annum, in the case of base rate loans, based upon our Consolidated Leverage Ratio at such time. Amounts borrowed under the Amended Credit Agreement may be prepaid at any time without premium or penalty. We are required to prepay the amounts outstanding under the Amended Credit Agreement in certain circumstances, including a requirement to pay all amounts outstanding 90 days prior to the Convertible Indebtedness Maturity Date (as defined in the Amended Credit Agreement) unless (1) the Convertible Indebtedness Maturity Date is waived or extended to a later date, (2) the Company can demonstrate (a) Liquidity (as defined in the Amended Credit Agreement) in an amount at least equal to the principal amount due on the Convertible Indebtedness Maturity Date, and (b) financial covenant compliance after giving effect to such payments and any additional indebtedness incurred on a pro forma basis, or (3) this requirement is waived by the Required Lenders (as defined in the Amended Credit Agreement). In addition, we have the right to permanently reduce or terminate the unused portion of the commitments provided under the Amended Credit Agreement at any time. The loans and obligations under the Amended Credit Agreement are secured pursuant to a Second Amended and Restated Security Agreement and a Second Amended and Restated Pledge Agreement (the “Pledge Agreement”) with Bank of America, N.A. as collateral agent, pursuant to which the Company and the subsidiary guarantors grant Bank of America, N.A., for the ratable benefit of the lenders under the Amended Credit Agreement, a first-priority lien, subject to permitted liens, on substantially all of the personal property assets of the Company and the subsidiary guarantors, and a pledge of 100% of the stock or other equity interests in all domestic subsidiaries and 65% of the stock or other equity interests in each “material first-tier foreign subsidiary” (as defined in the Pledge Agreement). The Amended Credit Agreement contains usual and customary representations and warranties; affirmative and negative covenants, which include limitations on liens, investments, additional indebtedness, and restricted payments; and two quarterly financial covenants as follows: (i) a maximum Consolidated Leverage Ratio (defined as the ratio of debt to consolidated EBITDA) ranging from 3.25 to 1.00 to 3.75 to 1.00, depending on the measurement period, and (ii) a minimum Consolidated Interest Coverage Ratio (defined as the ratio of consolidated EBITDA to interest) of 3.50 to 1.00. Consolidated EBITDA for purposes of the financial covenants is calculated on a continuing operations basis and includes adjustments to add back, among other items, share-based compensation costs, non-cash goodwill impairment charges, non-cash restructuring charges, and pro forma historical EBITDA for businesses acquired. At December 31, 2017 , we were in compliance with these financial covenants with a Consolidated Leverage Ratio of 3.02 to 1.00 and a Consolidated Interest Coverage Ratio of 12.43 to 1.00. Borrowings outstanding under the Amended Credit Agreement at December 31, 2017 totaled $105.0 million . These borrowings carried a weighted average interest rate of 3.7% , including the impact of the interest rate swap described in Note 11 “Derivative Instruments and Hedging Activity" that was in effect at December 31, 2017. Borrowings outstanding under the Amended Credit Agreement at December 31, 2016 were $68.0 million and carried a weighted average interest rate of 2.5% , including the impact of the interest rate swap that was in effect at December 31, 2016. The borrowing capacity under the revolving credit facility is reduced by any outstanding borrowings under the revolving credit facility and outstanding letters of credit. At December 31, 2017 , we had outstanding letters of credit totaling $1.9 million , which are primarily used as security deposits for our office facilities. As of December 31, 2017 , the unused borrowing capacity under the revolving credit facility was $393.1 million . Promissory Note due 2024 On June 30, 2017, in conjunction with our purchase of an aircraft related to the acquisition of Innosight, we assumed, from the sellers of the aircraft, a promissory note with an outstanding principal balance of $5.1 million . The principal balance of the promissory note is subject to scheduled monthly principal payments until the maturity date of March 1, 2024 , at which time a final payment of $1.5 million , plus any accrued and unpaid interest, will be due. Under the terms of the promissory note, we will pay interest on the outstanding principal amount at a rate of one -month LIBOR plus 1.97% per annum. The obligations under the promissory note are secured pursuant to a Loan and Aircraft Security Agreement with Banc of America Leasing & Capital, LLC, which grants the lender a first priority security interest in the aircraft. At December 31, 2017 , the outstanding principal amount of the promissory note was $4.9 million . As of December 31, 2017 , the aircraft had a carrying amount of $6.5 million .

Capital Structure

Capital Structure	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Capital Structure	Capital Structure Preferred Stock We are authorized to issue up to 50,000,000 shares of preferred stock. Our certificate of incorporation authorizes our board of directors, without any further stockholder action or approval, to issue these shares in one or more classes or series, to establish from time to time the number of shares to be included in each class or series, and to fix the rights, preferences and privileges of the shares of each wholly unissued class or series and any of its qualifications, limitations or restrictions. As of December 31, 2017 and 2016 , no such preferred stock has been approved or issued. Common Stock We are authorized to issue up to 500,000,000 shares of common stock, par value $.01 per share. The holders of common stock are entitled to one vote for each share held of record on each matter submitted to a vote of stockholders. Subject to the rights and preferences of the holders of any series of preferred stock that may at the time be outstanding, holders of common stock are entitled to such dividends as our board of directors may declare. In the event of any liquidation, dissolution or winding-up of our affairs, after payment of all of our debts and liabilities and subject to the rights and preferences of the holders of any series of preferred stock that may at the time be outstanding, holders of common stock will be entitled to receive the distribution of any of our remaining assets.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Basic earnings per share excludes dilution and is computed by dividing net income by the weighted average number of common shares outstanding for the period, excluding unvested restricted common stock. Diluted earnings per share reflects the potential reduction in earnings per share that could occur if securities or other contracts to issue common stock were exercised or converted into common stock under the treasury stock method. Such securities or other contracts include unvested restricted stock awards, outstanding common stock options, convertible senior notes, and outstanding warrants, to the extent dilutive. In periods for which we report a net loss from continuing operations, diluted weighted average common shares outstanding excludes all potential common stock equivalents as their impact on diluted net loss from continuing operations per share would be anti-dilutive. Earnings (loss) per share under the basic and diluted computations are as follows: Year Ended December 31, 2017 2016 2015 Net income (loss) from continuing operations $ (170,505 ) $ 39,480 $ 61,895 Income (loss) from discontinued operations, net of tax 388 (1,863 ) (2,843 ) Net income (loss) $ (170,117 ) $ 37,617 $ 59,052 Weighted average common shares outstanding—basic 21,439 21,084 22,136 Weighted average common stock equivalents — 340 464 Weighted average common shares outstanding—diluted 21,439 21,424 22,600 Net earnings (loss) per basic share: Net income (loss) from continuing operations $ (7.95 ) $ 1.87 $ 2.80 Income (loss) from discontinued operations, net of tax 0.02 (0.09 ) (0.13 ) Net income (loss) $ (7.93 ) $ 1.78 $ 2.67 Net earnings (loss) per diluted share: Net income (loss) from continuing operations $ (7.95 ) $ 1.84 $ 2.74 Income (loss) from discontinued operations, net of tax 0.02 (0.08 ) (0.13 ) Net income (loss) $ (7.93 ) $ 1.76 $ 2.61 The number of anti-dilutive securities excluded from the computation of the weighted average common stock equivalents presented above were as follows: As of December 31, 2017 2016 2015 Unvested restricted stock awards 636 2 21 Outstanding common stock options 194 — — Convertible senior notes 3,129 3,129 3,129 Warrants related to the issuance of convertible senior notes 3,129 3,129 3,129 Total anti-dilutive securities 7,088 6,260 6,279 See Note 7 “Financing Arrangements” for further information on the convertible senior notes and warrants related to the issuance of convertible notes. We currently have a share repurchase program permitting us to repurchase up to $125 million of our common stock through October 31, 2018 (the "Share Repurchase Program"). The amount and timing of the repurchases will be determined by management and will depend on a variety of factors, including the trading price of our common stock, capacity under our credit facility, general market and business conditions, and applicable legal requirements. No shares were repurchased under this program in 2017. In 2016, we repurchased and retired 982,192 shares for $55.3 million , and in 2015, we repurchased and retired 583,880 shares for $34.6 million . As of December 31, 2017 , $35.1 million remains available for share repurchases.

Restructuring Charges

Restructuring Charges	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring Charges	Restructuring Charges In 2017, we incurred $6.2 million of pretax restructuring expense. This expense primarily consisted of the following charges: Severance - We incurred $3.7 million of severance expense as a result of workforce reductions to better align resources with market demand. Of the $3.7 million , $2.1 million related to our Healthcare segment, $1.1 million related to our Business Advisory segment, and $0.4 million related to our corporate operations. Office exit costs - We incurred $2.4 million of office exit costs primarily related to the accrual of remaining lease obligations, net of estimated sublease income, due to relocating our San Francisco office to a smaller space and consolidating our Chicago and New York offices, and accelerated depreciation on leasehold improvements for our San Francisco office. Of the $6.2 million pretax restructuring charge, $2.1 million was related to our Healthcare segment, $1.1 million was related to our Business Advisory segment, and $2.9 million was related to our corporate operations. In 2016, we incurred $9.6 million of pretax restructuring expense. This expense consisted of the following charges: Severance - We incurred $7.3 million of severance expense as a result of workforce reductions, of which $6.4 million was related to our Healthcare and Business Advisory segments to better align our resources with market demand and $0.9 million was related to our corporate infrastructure as a result of our Huron Legal divestiture. Office exit costs - We incurred $1.5 million of office exit costs primarily related to our Washington, D.C. space that we vacated in the fourth quarter of 2014. During the third quarter of 2016, we entered into a sublease agreement and adjusted our Washington, D.C. lease accrual to reflect the terms specified in the sublease agreement. Other - We also incurred $0.8 million of restructuring expense related to the wind down of our foreign consulting operations based in the Middle East and other exit costs. Of the $9.6 million pretax restructuring charge, $5.8 million was related to our Healthcare segment, $3.2 million was related to our corporate operations, and $0.6 million was related to our Business Advisory segment. In 2015, we incurred $3.3 million of pretax restructuring expense. This expense primarily consisted of the following charges: Severance - We incurred $2.8 million of severance expense as a result of workforce reductions to better align our resources with market demand. Office exit costs - We incurred $0.5 million of office exit costs primarily related to updated assumptions for the lease accrual of the Washington, D.C. space vacated in the fourth quarter of 2014. Of the $3.3 million pretax restructuring expense, $1.2 million was related to our Healthcare segment, $1.1 million was related to our All Other segment as we wound down our public sector consulting practice and our foreign consulting operations based in the Middle East, and $1.0 million was related to our corporate operations. The table below sets forth the changes in the carrying amount of our restructuring charge liability by restructuring type for the years ended December 31, 2017 and 2016 . Employee Costs Office Space Reductions Other Total Balance as of December 31, 2015 $ 2,323 $ 6,379 $ — $ 8,702 Additions (1) 9,082 57 585 9,724 Payments (5,906 ) (2,424 ) (482 ) (8,812 ) Adjustments (1) (317 ) 1,765 245 1,693 Non-cash items — (4 ) (324 ) (328 ) Balance as of December 31, 2016 5,182 5,773 24 10,979 Additions (1) 3,859 2,426 110 6,395 Payments (7,611 ) (2,860 ) 5 (10,466 ) Adjustments (1) (117 ) (973 ) (78 ) (1,168 ) Non-cash items (46 ) (119 ) (61 ) (226 ) Balance as of December 31, 2017 $ 1,267 $ 4,247 $ — $ 5,514 (1) Additions and adjustments for the years ended December 31, 2017 and 2016 include a gain of $1.0 million and a charge of $2.0 million , respectively, related to updated lease assumptions for vacated offices spaces directly related to discontinued operations. Refer to Note 3 "Discontinued Operations" for additional information on our discontinued operations. As of December 31, 2017 , our restructuring charge liability related to office space reductions of $4.2 million represented the present value of remaining lease payments, net of estimated sublease income, primarily for our vacated office spaces in Washington, D.C., Houston, Chicago, and San Francisco. This restructuring charge liability is included as a component of accrued expenses and other current liabilities and deferred compensation and other liabilities. All of the $1.3 million restructuring charge liability related to employee costs at December 31, 2017 is expected to be paid in 2018. The restructuring charge liability related to employee costs is included as a component of accrued payroll and related benefits.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activity	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activity	Derivative Instruments and Hedging Activity On April 4, 2013, we entered into a forward amortizing interest rate swap agreement effective March 31, 2014 which ended August 31, 2017 . We entered into this derivative instrument to hedge against the interest rate risks of our variable-rate borrowings. The swap had an initial notional amount of $60.0 million and amortized quarterly until April 2016. In April 2016, the notional amount of this interest rate swap increased to $86.0 million and continued to amortize quarterly until it expired in August 2017. Under the terms of the interest rate swap agreement, we received from the counterparty interest on the notional amount based on one -month LIBOR and we paid to the counterparty a fixed rate of 0.985% . On June 22, 2017, we entered into a forward interest rate swap agreement effective August 31, 2017 and ending August 31, 2022 , with a notional amount of $50.0 million . We entered into this derivative instrument to continue to hedge against the interest rate risks of our variable-rate borrowings. Under the terms of the interest rate swap agreement, we receive from the counterparty interest on the notional amount based on one -month LIBOR and we pay to the counterparty a fixed rate of 1.900% . We recognize all derivative instruments as either assets or liabilities at fair value on the balance sheet. We have designated these derivative instruments as cash flow hedges. Therefore, changes in the fair value of the derivative instruments are recorded to other comprehensive income (“OCI”) to the extent effective and reclassified into interest expense upon settlement. The ineffective portion of the change in fair value of the derivative instruments is recognized in interest expense. Our interest rate swap agreement was effective during the year ended December 31, 2017 . As of December 31, 2017 , it was anticipated that less than $0.1 million of the accumulated other comprehensive income, net of tax, currently recorded on our consolidated balance sheet will be reclassified into earnings within the next 12 months. The table below sets forth additional information relating to our interest rate swaps designated as cash flow hedging instruments as of December 31, 2017 and 2016 . Fair Value (Derivative Asset and Liability) As of December 31, Balance Sheet Location 2017 2016 Other non-current assets $ 581 $ — Accrued expenses $ 48 $ 54 All of our derivative instruments are transacted under the International Swaps and Derivatives Association (ISDA) master agreements. These agreements permit the net settlement of amounts owed in the event of default and certain other termination events. Although netting is permitted, it is our policy to record all derivative assets and liabilities on a gross basis on our consolidated balance sheet. We do not use derivative instruments for trading or other speculative purposes. Refer to Note 13 “Other Comprehensive Income (Loss)” for additional information on our derivative instrument.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments Certain of our assets and liabilities are measured at fair value. Fair value is defined as the price that would be received to sell an asset or the price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. GAAP establishes a fair value hierarchy for inputs used in measuring fair value and requires companies to maximize the use of observable inputs and minimize the use of unobservable inputs. The fair value hierarchy consists of three levels based on the objectivity of the inputs as follows: Level 1 Inputs Quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 Inputs Quoted prices in active markets for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; inputs other than quoted prices that are observable for the asset or liability; or inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3 Inputs Unobservable inputs for the asset or liability, and include situations in which there is little, if any, market activity for the asset or liability. The table below sets forth our fair value hierarchy for our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2017 and 2016 . Level 1 Level 2 Level 3 Total December 31, 2017 Assets: Interest rate swaps $ — $ 533 $ — $ 533 Promissory note — — 1,078 1,078 Convertible debt investment — — 39,904 39,904 Deferred compensation assets — 17,786 — 17,786 Total assets $ — $ 18,319 $ 40,982 $ 59,301 Liabilities: Contingent consideration for business acquisitions $ — $ — $ 22,828 $ 22,828 Total liabilities $ — $ — $ 22,828 $ 22,828 December 31, 2016 Assets: Promissory note $ — $ — $ 2,325 $ 2,325 Convertible debt investment — — 34,675 34,675 Deferred compensation assets — 16,408 — 16,408 Total assets $ — $ 16,408 $ 37,000 $ 53,408 Liabilities: Interest rate swaps $ — $ 54 $ — $ 54 Contingent consideration for business acquisitions — — 8,827 8,827 Total liabilities $ — $ 54 $ 8,827 $ 8,881 Interest rate swaps: The fair values of our interest rate swaps were derived using estimates to settle the interest rate swap agreements, which are based on the net present value of expected future cash flows on each leg of the swaps utilizing market-based inputs and discount rates reflecting the risks involved. Promissory note : As part of the consideration received for the sale of our Accounting Advisory practice on December 30, 2011, we received a $3.5 million promissory note payable over four years. During the fourth quarter of 2017, we amended and restated the note which established scheduled annual principal payments, increased the interest rate, reduced the outstanding principal amount by $0.5 million , and extended the maturity date to September 30, 2020. Additionally, at the closing of this amended promissory note, we received a $1.0 million principal payment. As a result of the amendment, we recorded a $0.3 million fair value remeasurement loss on the promissory note which is recorded in other income (expense), net in the consolidated statement of operations. The scheduled principal payments will be paid to us annually until the maturity date of September 30, 2020 , at which time the remaining principal balance and any accrued interest is due. The fair value of the note is based on the net present value of the projected cash flows using a discount rate of 10% , which accounts for the risks associated with the amended note. This fair value measurement is based on significant inputs not observable in the market and thus represent Level 3 inputs. As of December 31, 2017 , $0.5 million is recorded in prepaid expenses and other current assets and represents the present value of the payments expected to be received in the next 12 months, and the remaining $0.6 million is recorded in other non-current assets. As of December 31, 2017, there was $1.0 million principal amount outstanding under the promissory note. The table below sets forth the changes in the balance of the promissory note for the years ended December 31, 2017 and 2016 . Promissory Note Balance as of December 31, 2015 $ 2,309 Interest payments received (191 ) Change in fair value of promissory note 207 Balance as of December 31, 2016 2,325 Interest payments received (185 ) Principal payments received (1,177 ) Change in fair value of promissory note 115 Balance as of December 31, 2017 $ 1,078 Convertible debt investment: In 2014 and 2015, we invested $27.9 million , in the form of zero coupon convertible debt, in Shorelight Holdings, LLC (“Shorelight”), the parent company of Shorelight Education, a U.S.-based company that partners with leading nonprofit universities to increase access to and retention of international students, boost institutional growth, and enhance an institution’s global footprint. The notes will mature on July 1, 2020 , unless converted earlier. To determine the appropriate accounting treatment for our investment, we performed a variable interest entity (“VIE”) analysis and concluded that Shorelight does not meet the definition of a VIE. We also reviewed the characteristics of our investment to confirm that the convertible notes are not in-substance common stock that would warrant equity method accounting. After we reviewed all of the terms of the investment, we concluded the appropriate accounting treatment to be that of an available-for-sale debt security. The investment is carried at fair value with unrealized holding gains and losses excluded from earnings and reported in other comprehensive income. We estimated the fair value of our investment using a Monte Carlo simulation model, cash flow projections discounted at a risk-adjusted rate, and certain assumptions related to equity volatility, default probability, and recovery rate, all of which are Level 3 inputs. The use of alternative estimates and assumptions could increase or decrease the estimated fair value of the investment, which would result in different impacts to our consolidated balance sheet and comprehensive income. Actual results may differ from our estimates. The fair value of the convertible debt investment is recorded in long-term investment. The table below sets forth the changes in the balance of the convertible debt investment for the years ended December 31, 2017 and 2016 . Convertible Debt Investment Balance as of December 31, 2015 $ 34,831 Change in fair value of convertible debt investment (156 ) Balance as of December 31, 2016 34,675 Change in fair value of convertible debt investment 5,229 Balance as of December 31, 2017 $ 39,904 Deferred compensation assets: We have a non-qualified deferred compensation plan (the "Plan") for the members of our board of directors and a select group of our employees. The deferred compensation liability is funded by the Plan assets, which consist of life insurance policies maintained within a trust. The cash surrender value of the life insurance policies approximates fair value, and is based on third-party broker statements which provide the fair value of the life insurance policies' underlying investments, which are Level 2 inputs. The cash surrender value of the life insurance policies is invested primarily in mutual funds. The Plan assets are included in other non-current assets on our consolidated balance sheet. Realized and unrealized gains (losses) from the deferred compensation assets are recorded to other income (expense), net in our consolidated statements of operations. Contingent consideration for business acquisitions: We estimate the fair value of acquisition-related contingent consideration using either a probability-weighted assessment of the specific financial performance targets being achieved or a Monte Carlo simulation model, as appropriate. These fair value measurements are based on significant inputs not observable in the market and thus represent Level 3 inputs. The significant unobservable inputs used in the fair value measurements of our contingent consideration are our measures of the estimated payouts based on internally generated financial projections on a probability-weighted basis and discount rates, which typically reflect a risk-free rate. The fair value of the contingent consideration is reassessed quarterly based on assumptions used in our latest projections and input provided by practice leaders and management. Any change in the fair value estimate is recorded in our consolidated statement of operations for that period. The use of alternative estimates and assumptions could increase or decrease the estimated fair value of our contingent consideration liability, which would result in different impacts to our consolidated balance sheets and consolidated statements of operations. Actual results may differ from our estimates. Refer to Note 4 “Acquisitions” for information on the acquisitions completed in 2017 , 2016 , and 2015 . The table below sets forth the changes in the balance of the contingent consideration for business acquisitions for the years ended December 31, 2017 and 2016 . Contingent Consideration for Business Acquisitions Balance as of December 31, 2015 $ 2,063 Acquisitions 8,754 Remeasurement of contingent consideration for business acquisitions (1,990 ) Balance as of December 31, 2016 8,827 Acquisitions 15,489 Payments (2,938 ) Remeasurement of contingent consideration for business acquisitions 1,111 Unrealized loss due to foreign currency translation 339 Balance as of December 31, 2017 $ 22,828 Financial assets and liabilities not recorded at fair value are as follows: Senior Secured Credit Facility The carrying value of our borrowings outstanding under our senior secured credit facility is stated at cost. Our carrying value approximates fair value, using Level 2 inputs, as the senior secured credit facility bears interest at variable rates based on current market rates as set forth in the Amended Credit Agreement. Refer to Note 7 “Financing Arrangements” for additional information on our senior secured credit facility. Promissory Note due 2024 The carrying value of our promissory note due 2024 is stated at cost. Our carrying value approximates fair value, using Level 2 inputs, as the promissory note bears interest at rates based on current market rates as set forth in the terms of the promissory note. Refer to Note 7 “Financing Arrangements” for additional information on our promissory note due 2024. Convertible Notes The carrying amount and estimated fair value of the Convertible Notes are as follows: December 31, 2017 December 31, 2016 Carrying Amount Estimated Fair Value Carrying Estimated 1.25% convertible senior notes due 2019 $ 233,140 $ 232,578 $ 224,065 $ 245,018 The differences between the $250 million principal amount of the Convertible Notes and the carrying amounts shown above represent the unamortized debt discount and issuance costs. As of December 31, 2017 and 2016 , the carrying value of the equity component of $39.3 million was unchanged from the date of issuance. Refer to Note 7 “Financing Arrangements” for additional information on our Convertible Notes. The estimated fair value of the Convertible Notes was determined based on the quoted bid price of the Convertible Notes in an over-the-counter market, which is a Level 2 input, on the last day of trading for the quarters ended December 31, 2017 and 2016 . Based on the closing price of our common stock of $40.45 on December 31, 2017 , the if-converted value of the Convertible Notes was less than the principal amount. Cash and cash equivalents are stated at cost, which approximates fair market value. The carrying values of all other financial instruments not described above reasonably approximate fair market value due to the nature of the financial instruments and the short-term maturity of these items.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) The table below sets forth the components of accumulated other comprehensive income (loss), net of tax for the years ended December 31, 2017 , 2016 , and 2015 . Foreign Currency Translation Available-for- Sale Investments Cash Flow Hedges (1) Total Balance as of December 31, 2014 $ (2,334 ) $ (250 ) $ (71 ) $ (2,655 ) Foreign currency translation adjustment, net of tax of $0 (403 ) — — (403 ) Reclassification adjustment into earnings, net of tax of $0 (2) 2,220 — — 2,220 Unrealized gain on investments, net of tax of $(2,709) — 4,435 — 4,435 Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $327 — — (492 ) (492 ) Reclassification adjustment into earnings, net of tax of $(320) — — 480 480 Balance as of December 31, 2015 (517 ) 4,185 (83 ) 3,585 Foreign currency translation adjustment, net of tax of $0 64 — — 64 Unrealized loss on investments, net of tax of $59 — (97 ) — (97 ) Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $122 — — (179 ) (179 ) Reclassification adjustment into earnings, net of tax of $(161) — — 242 242 Balance as of December 31, 2016 (453 ) 4,088 (20 ) 3,615 Foreign currency translation adjustment, net of tax of $0 1,602 — — 1,602 Unrealized gain on investments: Change in fair value, net of tax of $(998) — 4,231 — 4,231 Reclassification adjustment into retained earnings (3) — 493 — 493 Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $(106) — — 366 366 Reclassification adjustment into earnings, net of tax of $(46) — — 69 69 Reclassification adjustment into retained earnings (3) — — (6 ) (6 ) Balance as of December 31, 2017 $ 1,149 $ 8,812 $ 409 $ 10,370 (1) The before tax amounts reclassified from accumulated other comprehensive income (loss) related to our cash flow hedges are recorded to interest expense, net of interest income. (2) In connection with the divestiture of Huron Legal, which included the sale of certain wholly-owned foreign subsidiaries, we reclassified $2.2 million of accumulated translation losses to net income from discontinued operations. (3) Upon adoption of ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, we reclassified $0.5 million of stranded tax effects, which resulted from the enactment of the 2017 Tax Reform, from accumulated other comprehensive income to retained earnings. Refer to Note 2 "Summary of Significant Accounting Policies" for additional information on the adoption of ASU 2018-02.

Employee Benefit and Deferred C

Employee Benefit and Deferred Compensation Plans	12 Months Ended
	Dec. 31, 2017
Postemployment Benefits [Abstract]
Employee Benefit and Deferred Compensation Plans	Employee Benefit and Deferred Compensation Plans We sponsor a qualified defined contribution 401(k) plan covering substantially all of our employees. Under the plan, employees are entitled to make pretax contributions and/or Roth post-tax contributions up to the annual maximums established by the Internal Revenue Service. We match an amount equal to the employees’ contributions up to 6% of the employees’ salaries. Our matching contributions, including those related to our discontinued operations, for the years ended December 31, 2017 , 2016 , and 2015 were $20.0 million , $19.4 million , and $17.6 million , respectively. We have a non-qualified deferred compensation plan (the “Plan”) that is administered by our board of directors or a committee designated by the board of directors. Under the Plan, members of the board of directors and a select group of our employees may elect to defer the receipt of their director retainers and meeting fees or base salary and bonus, as applicable. Additionally, we may credit amounts to a participant’s deferred compensation account in accordance with employment or other agreements entered into between us and the participant. At our sole discretion, we may, but are not required to, credit any additional amount we desire to any participant’s deferred compensation account. Amounts credited are subject to vesting schedules set forth in the Plan, employment agreement, or any other agreement entered into between us and the participant. The deferred compensation liability at December 31, 2017 and 2016 was $17.7 million and $16.4 million , respectively. This deferred compensation liability is funded by the Plan assets.

Equity Incentive Plans

Equity Incentive Plans	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Incentive Plans	Equity Incentive Plans In 2012, Huron adopted the 2012 Omnibus Incentive Plan (the “2012 Plan”), in order to increase the number of shares of common stock available as equity compensation to employees, non-employee directors, and independent contractors, and to make certain updates to reflect changes in market practices. The 2012 Plan replaced, on a prospective basis, our 2004 Omnibus Stock Plan (the "2004 Plan") such that future grants will be granted under the 2012 Plan and any outstanding awards granted under the 2004 Plan that are cancelled, expired, forfeited, settled in cash, or otherwise terminated without a delivery of shares to the participant will not become available for grant under the 2012 Plan. The 2012 Plan permits the grant of stock options, stock appreciation rights, restricted stock, performance shares and other share-based or cash-based awards valued in whole or in part by reference to, or otherwise based on, our common stock. The 2012 Plan was amended on May 2, 2014 to increase the number of shares authorized for issuance by 850,000 shares. On May 5, 2017, an amendment and restatement of the 2012 Plan was approved by shareholders to increase the number of shares authorized for issuance by 804,000 shares. As of December 31, 2017 , approximately 1.3 million shares remain available for issuance under the 2012 Plan. On May 1, 2015, we adopted the Stock Ownership Participation Program (the “SOPP”), which is available to Huron employees below the managing director level who do not receive equity-based awards as part of their normal compensation plan. Under the SOPP, eligible employees may elect to use after-tax payroll deductions, or cash contributions, to purchase shares of the Company’s common stock on certain designated purchase dates. Employees who purchase stock under the SOPP are granted restricted stock equal to 25% of their purchased shares. Vesting of the restricted stock is subject to both a time-based vesting schedule and a requirement that the purchased shares be held for a specified holding period. The initial number of shares available for issuance under the SOPP was 300,000 . Prior to adopting the SOPP, the matching share grants and the employee purchased shares under the stock ownership participation program were governed by the 2012 Plan. As of December 31, 2017 , approximately 0.1 million shares remain available for issuance under the SOPP. It has been our practice to issue shares of common stock upon exercise of stock options and granting of restricted stock from authorized but unissued shares, with the exception of the SOPP under which shares are issued from treasury stock. Certain grants of restricted stock under the 2012 Plan may be issued from treasury stock at the direction of the Compensation Committee. The Compensation Committee of the board of directors has the responsibility of interpreting the 2012 Plan and SOPP and determining all of the terms and conditions of awards made under the plans, including when the awards will become exercisable or otherwise vest. In 2013, the Compensation Committee amended certain share-based awards outstanding under our 2012 Plan and our 2004 Plan to provide for a retirement eligibility provision. Under this provision, eligible employees who have reached 62 years of age and have completed seven years of employment with Huron will continue vesting in their share-based awards after retirement, subject to certain conditions. This retirement eligibility provision will also apply to future awards granted to eligible employees under the 2012 Plan. Total share-based compensation cost recognized for the years ended December 31, 2017 , 2016 , and 2015 was $14.8 million , $16.6 million , and $19.2 million , respectively, with related income tax benefits of $5.8 million , $6.4 million , and $7.6 million , respectively. As of December 31, 2017 , there was $17.6 million of total unrecognized compensation cost related to nonvested share-based awards. This cost is expected to be recognized over a weighted average period of 2.2 years. Restricted Stock Awards The grant date fair values of our restricted stock awards are measured based on the fair value of our common stock at grant date and amortized into expense over the service period. Subject to acceleration under certain conditions, the majority of our restricted stock vests annually over four years. The table below summarizes the restricted stock activity for the year ended December 31, 2017 . Number of Shares Weighted Average Grant Date Fair Value (in dollars) 2012 Omnibus Incentive Plan Stock Ownership Participation Program Total Nonvested restricted stock at December 31, 2016 610 12 622 $ 59.77 Granted 270 14 284 $ 42.11 Vested (247 ) (9 ) (256 ) $ 57.80 Forfeited (72 ) (4 ) (76 ) $ 59.18 Nonvested restricted stock at December 31, 2017 561 13 574 $ 51.97 The aggregate fair value of restricted stock that vested during the years ended December 31, 2017 , 2016 , and 2015 was $11.1 million , $14.9 million , and $23.9 million , respectively. The weighted average grant date fair value per share of restricted stock granted during 2016 and 2015 was $56.28 and $66.21 , respectively. Performance-based Share Awards During 2017 , 2016 , and 2015 , the Company granted performance-based share awards to our named executive officers and certain managing directors. The total number of shares earned by recipients of these awards is contingent upon meeting practice specific and Company-wide performance goals. Following the performance period, the awards are subject to the completion of a service period, which is generally an additional one to three years. The earned awards vest on a graded vesting schedule over the service period. For certain performance awards, the recipients may earn additional shares of stock for performance achieved above the stated target. The grant date fair values of our performance-based share awards are measured based on the fair value of our common stock at grant date. Compensation cost is amortized into expense over the service period, including the performance period. The table below summarizes the performance-based stock activity for the year ended December 31, 2017 . All nonvested performance-based stock outstanding at December 31, 2016 and 2017 was granted under the 2012 Omnibus Incentive Plan. Number of Shares Weighted Average Grant Date Fair Value (in dollars) Nonvested performance-based stock at December 31, 2016 239 $ 58.47 Granted (1) 328 $ 42.75 Vested (85 ) $ 61.66 Forfeited (2) (129 ) $ 54.85 Nonvested performance-based stock at December 31, 2017 (3) 353 $ 44.45 (1) Shares granted in 2017 are presented at the stated target, which represents the base number of shares that could be earned. Actual shares earned may be below or, for certain grants, above the target based on the achievement of specific financial goals. (2) Forfeited shares include shares forfeited as a result of not meeting the performance criteria of the award as well as shares forfeited upon termination. (3) Of the 353,000 nonvested performance-based shares outstanding as of December 31, 2017 , approximately 316,000 shares were unearned and subject to achievement of specific financial goals. Once earned, the awards will be subject to time-based vesting according to the terms of the award. Based on 2017 financial results, approximately 235,000 of the 316,000 unearned shares will be forfeited in the first quarter of 2018 . The aggregate fair value of performance-based stock that vested during the years ended December 31, 2017 , 2016 , and 2015 was $3.6 million , $3.0 million , and $6.5 million , respectively. The weighted average grant date fair value per share of performance-based stock granted during 2016 and 2015 was $55.52 and $66.63 , respectively. Stock Options Prior to 2014, the Company granted stock option awards to certain named executive officers. No stock option awards were granted in 2017, 2016, or 2015. The exercise prices of stock options are equal to the fair value of a share of common stock on the date of grant. Subject to acceleration under certain conditions, our stock options vest annually over four years. All stock options have a 10 -year contractual term. Stock option activity for the year ended December 31, 2017 was as follows: Number of Options (in thousands) Weighted Average Exercise Price (in dollars) Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2016 194 $ 29.06 4.3 $ 4.2 Granted — Exercised — Forfeited or expired — Outstanding at December 31, 2017 (1) 194 $ 29.06 3.3 $ 2.2 Exercisable at December 31, 2017 194 $ 29.06 3.3 $ 2.2 (1) Of the 194,000 outstanding options, approximately 157,000 were granted under the 2004 Omnibus Stock Plan, and the remaining 37,000 options were granted under the 2012 Omnibus Incentive Plan. No options were exercised in 2017. The aggregate intrinsic value of options exercised during 2016 was $0.1 million . No options were exercised in 2015.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes On December 22, 2017, the President of the United States signed into law the Tax Cuts and Jobs Act (“2017 Tax Reform”), a tax reform bill which, among other items, reduces the current corporate federal income tax rate from 35% to 21% and moves from a worldwide tax system to a territorial system. The rate reduction is effective January 1, 2018. As a result of the enactment of the legislation in 2017, we have estimated the remeasurement of our net deferred taxes based on the new lower tax rate, as well as provided for additional one-time income tax expense estimates primarily related to the transition tax on accumulated foreign earnings and elimination of foreign tax credits for dividends that are subject to the 100 percent exemption in our consolidated financial statements as of and for the year ended December 31, 2017. Our provisional analysis resulted in $8.8 million of additional income tax expense for the year ended December 31, 2017. Of the $8.8 million , $7.9 million related to the remeasurement of our deferred tax balances at the lower federal income tax rate; $0.6 million related to the transition tax on accumulated foreign earnings, net of applicable foreign tax credits; and $0.3 million related to withholding tax on outside basis differences due to our change in assertion for permanent reinvestment. The impacts on our financial statements as a result of 2017 Tax Reform are considered provisional and are based on the information that is currently available. These provisional results may be subject to future adjustments as additional analysis is anticipated based on technical corrections and regulatory interpretations to come. We expect to finalize the analysis as soon as practicable, but, in accordance with Staff Accounting Bulletin (“SAB”) No. 118, which was issued as a result of 2017 Tax Reform, not later than one year from the enactment date. Any changes to our provisional analysis will be included as an adjustment to tax expense or benefit in the period the amounts are determined. The income tax expense for continuing operations for the years ended December 31, 2017 , 2016 , and 2015 consists of the following: Year Ended December 31, 2017 2016 2015 Current: Federal $ (635 ) $ 15,726 $ 4,806 State 545 1,623 2,380 Foreign 2,040 1,021 350 Total current 1,950 18,370 7,536 Deferred: Federal (46,103 ) 1,662 12,450 State (6,576 ) (274 ) 1,482 Foreign (1,270 ) (81 ) 202 Total deferred (53,949 ) 1,307 14,134 Income tax expense for continuing operations $ (51,999 ) $ 19,677 $ 21,670 The components of income from continuing operations before taxes were as follows: Year Ended December 31, 2017 2016 2015 U.S. $ (221,137 ) $ 56,141 $ 85,164 Foreign (1,367 ) 3,016 (1,599 ) Total $ (222,504 ) $ 59,157 $ 83,565 A reconciliation of the U.S. statutory income tax rate to our effective tax rate for continuing operations is as follows: Year Ended December 31, 2017 2016 2015 Percent of pretax income from continuing operations: At U.S. statutory tax rate 35.0 % 35.0 % 35.0 % State income taxes, net of federal benefit 2.7 1.7 4.6 Goodwill impairment charges (10.2 ) — — U.S. federal rate change (3.4 ) — — Transition tax on accumulated foreign earnings, net of credits (0.3 ) — — Stock-based compensation (0.8 ) — — Meals and entertainment (0.3 ) 1.1 0.6 Valuation allowance (0.2 ) (3.2 ) 0.5 Foreign source income 0.1 (0.5 ) 0.5 Tax credits / Section 199 Deduction 0.2 (1.1 ) (1.0 ) Net tax benefit related to “check-the-box” election (1) 1.2 — (14.7 ) Other (0.6 ) 0.3 0.4 Effective income tax rate for continuing operations 23.4 % 33.3 % 25.9 % (1) In the fourth quarter of 2015, we made a tax election to classify two of our wholly-owned foreign subsidiaries as disregarded entities for U.S. federal income tax purposes (commonly referred to as a “check-the-box” election). As a result of this election, we realized an income tax benefit of $13.0 million , of which $0.7 million is unrecognized, resulting in a net recognized tax benefit of $12.3 million . Due to the expiration of statute of limitations, in the third quarter of 2017, we recognized a $2.7 million tax benefit, including the reversal of accrued interest and penalties, related to a previously unrecognized tax benefit from our "check-the-box" election made in 2014 to treat one of our wholly-owned foreign subsidiaries as a disregarded entity for U.S federal income tax purposes. The effective tax rate for discontinued operations in 2017 was 60.0% , based on tax expense of $0.6 million and pretax income from discontinued operations of $1.0 million , and was higher than the statutory tax rate primarily due to the settlement of foreign tax audits. The effective tax rate for discontinued operations in 2016 was (33.4)% , based on tax benefits of $0.9 million and a pretax loss from discontinued operations of $2.8 million , and was lower than the statutory tax rate primarily due to an increase in the valuation allowance for foreign tax credits. The effective tax rate for discontinued operations in 2015 was 169.0% , based on tax expense of $1.8 million and a pretax loss from discontinued operations of $1.1 million , and was higher than the statutory tax rate primarily due to the tax expense recognized from the sale of the Huron Legal segment. Refer to Note 3 "Discontinued Operations" for further detail on the sale of the Huron Legal segment. The net deferred tax liabilities for continuing operations at December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Deferred tax assets: Share-based compensation $ 5,674 $ 10,151 Accrued payroll and other liabilities 7,010 10,004 Intangibles and goodwill 2,137 — Deferred lease incentives 4,352 4,666 Convertible note hedge transactions 250 12,197 Revenue recognition 1,586 1,983 Restructuring charge liability 1,104 2,230 Net operating loss carry-forwards 495 92 Tax credits 1,918 1,804 Other 882 1,934 Total deferred tax assets 25,408 45,061 Valuation allowance (1,247 ) (626 ) Net deferred tax assets 24,161 44,435 Deferred tax liabilities: Prepaid expenses (1,229 ) (2,500 ) Property and equipment (4,031 ) (2,933 ) Intangibles and goodwill — (60,411 ) Convertible note discount (3 ) (11,586 ) Convertible debt investment (3,110 ) (2,600 ) Other (133 ) (38 ) Total deferred tax liabilities (8,506 ) (80,068 ) Net deferred tax asset (liability) for continuing operations $ 15,655 $ (35,633 ) As of December 31, 2017 and 2016 , we had valuation allowances of $1.2 million and $0.6 million , respectively, primarily due to uncertainties relating to the ability to utilize deferred tax assets recorded for foreign losses. The increase in valuation allowances in 2017 primarily related to increases of net operating losses in jurisdictions where the net operating loss credits cannot be benefited and valuation allowances recorded on certain tax credits. We have federal and state tax credit carry-forwards of $1.9 million which expire in 2022 and 2019 , respectively. We have no federal net operating losses or state net operating loss carry-forwards as of December 31, 2017. We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position are measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate resolution. A reconciliation of our beginning and ending amount of unrecognized tax benefits is as follows: Unrecognized Tax Benefits Balance at January 1, 2015 $ 2,488 Additions based on tax positions related to the current year 735 Balance at December 31, 2015 3,223 Additions based on tax positions related to the current year 117 Balance at December 31, 2016 3,340 Decrease due to lapse of statute of limitations (2,410 ) Decrease based on tax positions related to the prior year (117 ) Balance at December 31, 2017 $ 813 As of December 31, 2017 , we had $0.8 million of unrecognized tax benefits which would affect the effective tax rate of continuing operations if recognized. As of December 31, 2017 and 2016 , we had $0.1 million and $0.3 million accrued for the potential payment of interest and penalties. Accrued interest and penalties are recorded as a component of provision for income taxes on our consolidated statement of earnings. We file income tax returns with federal, state, local and foreign jurisdictions. Tax years 2013 through 2016 are subject to future examinations by federal tax authorities. Tax years 2010 through 2016 are subject to future examinations by state and local tax authorities. Currently, the Company is not under audit by any tax authority. Our foreign income tax filings are subject to future examinations by the local foreign tax authorities for tax years 2010 through 2016 .

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	Commitments, Contingencies and Guarantees Lease Commitments We lease office space under non-cancelable operating lease arrangements expiring on various dates through 2028, with various renewal options. Our principal executive offices located in Chicago, Illinois are under a lease expiring in September 2024 . We have a five -year renewal option that will allow us to continue to occupy this office space until September 2029 . Office facilities under operating leases include fixed or minimum payments plus, in some cases, scheduled base rent increases over the term of the lease. Certain leases require monthly payments of real estate taxes, insurance and other operating expenses applicable to the property. Some of the leases contain provisions whereby the future rental payments may be adjusted for increases in operating expenses above the specified amount. Rent expense, including operating costs and taxes, for the years ended December 31, 2017 , 2016 , and 2015 was $14.3 million , $11.5 million , and $12.3 million , respectively. Future minimum rental commitments under non-cancelable leases and sublease income as of December 31, 2017 , are as follows: Operating Lease Obligations Sublease Income 2018 $ 14,739 $ 1,316 2019 13,444 291 2020 12,266 — 2021 11,298 — 2022 10,409 — Thereafter 37,804 — Total $ 99,960 $ 1,607 Litigation From time to time, we are involved in legal proceedings and litigation arising in the ordinary course of business. As of the date of this Annual Report on Form 10-K, we are not a party to any litigation or legal proceeding that, in the current opinion of management, could have a material adverse effect on our financial position or results of operations. However, due to the risks and uncertainties inherent in legal proceedings, actual results could differ from current expected results. Guarantees Guarantees in the form of letters of credit totaling $1.9 million and $4.8 million were outstanding at December 31, 2017 and 2016 , respectively, primarily to support certain office lease obligations. In connection with certain business acquisitions, we may be required to pay post-closing consideration to the sellers if specific financial performance targets are met over a number of years as specified in the related purchase agreements. As of December 31, 2017 and 2016 , the total estimated fair value of our contingent consideration liabilities was $22.8 million and $8.8 million , respectively. To the extent permitted by law, our bylaws and articles of incorporation require that we indemnify our officers and directors against judgments, fines and amounts paid in settlement, including attorneys’ fees, incurred in connection with civil or criminal action or proceedings, as it relates to their services to us if such person acted in good faith. Although there is no limit on the amount of indemnification, we may have recourse against our insurance carrier for certain payments made.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segment Information	Segment Information Segments are defined as components of a company that engage in business activities from which they may earn revenues and incur expenses, and for which separate financial information is available and is evaluated regularly by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Our chief operating decision maker, who is our chief executive officer, manages the business under three operating segments, which are our reportable segments: Healthcare, Education, and Business Advisory. During the second quarter of 2017, we reorganized our internal financial reporting structure, which management uses to assess performance and allocate resources, by moving our Life Sciences practice from the Education and Life Sciences segment to the Business Advisory segment. The remaining Education and Life Sciences segment is now referred to as the Education segment. While our consolidated results have not been impacted, we have reclassified our historical segment information for consistent presentation. • Healthcare Our Healthcare segment has a depth of expertise in strategy and innovation, care transformation, financial and operational excellence, technology and analytics, and leadership development. We serve national and regional hospitals and integrated health systems, academic medical centers, community hospitals, and medical groups. Our solutions help clients evolve and adapt to the rapidly changing healthcare environment and achieve growth, optimize performance, enhance profitability, improve quality and clinical outcomes, and drive physician, patient, and employee engagement across the enterprise. We help organizations transform and innovate the delivery model to focus on patient wellness by improving quality outcomes, minimizing care variation and fundamentally improving patient and population health. Our consultants partner with clients to help build and sustain today’s business to invest in the future by reducing complexity, improving operational efficiency and growing market share. We enable the healthcare of the future by identifying, integrating and optimizing technology investments to collect data that transforms care delivery and improves patient outcomes. We also develop future leaders capable of driving meaningful operational and organizational change and who transform the patient experience. • Education Our Education segment provides management consulting and technology solutions to higher education institutions and academic medical centers. We partner with clients to address challenges relating to business and technology strategy, financial management, operational and organizational effectiveness, research administration, and regulatory compliance. Our institutional strategy, market research, budgeting and financial management, business operations and student lifecycle management solutions align missions with business priorities, improve quality and reduce costs institution-wide. Our technology strategy, enterprise applications, and analytic solutions transform and optimize operations, deliver time and cost savings, and enhance the student experience. Our research enterprise solutions assist clients in identifying and implementing institutional research strategy, optimizing clinical research operations, improving financial management and cost reimbursement, improving service to faculty, and mitigating risk compliance. • Business Advisory Our Business Advisory segment provides services to large and middle market, not-for-profit organizations, lending institutions, law firms, investment banks, and private equity firms. We assist clients in a broad range of industries and across the spectrum from healthy, well-capitalized companies to organizations in transition as well as creditors, equity owners, and other key constituents. Our Business Advisory professionals resolve complex business issues and enhance client enterprise value through a suite of services including capital advisory, transaction advisory, operational improvement, restructuring and turnaround, valuation, and dispute advisory. Our Enterprise Solutions and Analytics professionals deliver technology and analytic solutions that enable organizations to manage and optimize their financial performance, operational efficiency, and client or stakeholder experience. Our Strategy and Innovation professionals collaborate with clients across a range of industries to identify new growth opportunities, build new ventures and capabilities, and accelerate organizational change. Our Life Sciences professionals provide strategic solutions to help pharmaceutical, medical device, and biotechnology companies deliver more value to patients, payers, and providers, and comply with regulations. Segment operating income consists of the revenues generated by a segment, less the direct costs of revenue and selling, general and administrative expenses that are incurred directly by the segment. Unallocated corporate costs include costs related to administrative functions that are performed in a centralized manner that are not attributable to a particular segment. These administrative function costs include costs for corporate office support, office facility costs, costs relating to accounting and finance, human resources, legal, marketing, information technology, and company-wide business development functions, as well as costs related to overall corporate management. The tables below set forth information about our operating segments for the years ended December 31, 2017 , 2016 , and 2015 , along with the items necessary to reconcile the segment information to the totals reported in the accompanying consolidated financial statements. We do not present financial information by geographic area because our international operations are immaterial. Year Ended December 31, 2017 2016 2015 Healthcare: Revenues $ 356,909 $ 424,912 $ 446,887 Operating income $ 118,761 $ 147,903 $ 169,560 Segment operating income as a percentage of segment revenues 33.3 % 34.8 % 37.9 % Education: Revenues $ 167,908 $ 149,817 $ 134,009 Operating income $ 40,318 $ 38,310 $ 32,246 Segment operating income as a percentage of segment revenues 24.0 % 25.6 % 24.1 % Business Advisory: Revenues $ 207,753 $ 151,543 $ 116,892 Operating income $ 46,600 $ 29,382 $ 31,233 Segment operating income as a percentage of segment revenues 22.4 % 19.4 % 26.7 % All Other: (1) Revenues $ — $ — $ 1,222 Operating loss $ — $ — $ (1,718 ) Segment operating loss as a percentage of segment revenues N/A N/A N/M Total Company: Revenues $ 732,570 $ 726,272 $ 699,010 Reimbursable expenses 75,175 71,712 70,013 Total revenues and reimbursable expenses $ 807,745 $ 797,984 $ 769,023 Segment operating income $ 205,679 $ 215,595 $ 231,321 Items not allocated at the segment level: Other operating expenses 120,718 111,852 112,164 Litigation and other losses (gains), net 1,111 (1,990 ) (9,476 ) Depreciation and amortization 38,213 31,499 25,135 Goodwill impairment charges (2) 253,093 — — Other expense, net 15,048 15,077 19,933 Income (loss) from continuing operations before taxes $ (222,504 ) $ 59,157 $ 83,565 (1) During 2015, we wound down the businesses within our All Other operating segment, which consisted of our public sector consulting practice and our foreign consulting operations based in the Middle East. We did not generate any revenues from our All Other segment during 2016 and 2017. (2) The goodwill impairment charges are not allocated at the segment level because the underlying goodwill asset is reflective of our corporate investment in the segments. We do not include the impact of goodwill impairment charges in our evaluation of segment performance. N/M – Not Meaningful N/A – Not Applicable As of December 31, Segment Assets: 2017 2016 2015 Healthcare $ 70,097 $ 69,274 $ 84,088 Education 31,367 33,094 28,192 Business Advisory 58,217 43,151 29,609 Unallocated assets (1) 877,247 1,007,696 1,017,654 Total assets $ 1,036,928 $ 1,153,215 $ 1,159,543 (1) Unallocated assets includes goodwill and intangible assets and our convertible debt investment, as management does not evaluate these items at the segment level when assessing segment performance or allocating resources. Refer to Note 5 “Goodwill and Intangible Assets" and Note 12 "Fair Value of Financial Instruments" for further information on these assets. For the years ended December 31, 2017 , 2016 , and 2015 , substantially all of our revenues and long-lived assets were attributed to or located in the United States. At December 31, 2017 and 2016 , no single client accounted for greater than 10% of our combined receivables and unbilled services balances. During the years ended December 31, 2017 , 2016 , and 2015 , no single client generated greater than 10% of our consolidated revenues.

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	Valuation and Qualifying Accounts The table below sets forth the changes in the carrying amount of our allowances for doubtful accounts and unbilled services and valuation allowance for deferred tax assets for the years ended December 31, 2017 , 2016 , and 2015 . Beginning balance Additions (1) Deductions Ending balance Year ended December 31, 2015: Allowances for doubtful accounts and unbilled services $ 14,129 40,003 37,246 $ 16,886 Valuation allowance for deferred tax assets $ 2,431 1,212 1,401 $ 2,242 Year ended December 31, 2016: Allowances for doubtful accounts and unbilled services $ 16,886 48,901 44,528 $ 21,259 Valuation allowance for deferred tax assets $ 2,242 113 1,729 $ 626 Year ended December 31, 2017: Allowances for doubtful accounts and unbilled services $ 21,259 43,888 40,648 $ 24,499 Valuation allowance for deferred tax assets $ 626 793 172 $ 1,247 (1) Additions to allowances for doubtful accounts and unbilled services are charged to revenues to the extent the provision relates to fee adjustments and other discretionary pricing adjustments. To the extent the provision relates to a client’s inability to make required payments on accounts receivables, the provision is charged to operating expenses. Additions also include allowances acquired in business acquisitions, which were not material in any period presented.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (unaudited)	Selected Quarterly Financial Data (Unaudited) Quarter Ended 2017 Mar. 31 Jun. 30 Sep. 30 Dec. 31 Revenues $ 188,849 $ 181,418 $ 176,376 $ 185,927 Reimbursable expenses 16,950 20,930 17,982 19,313 Total revenues and reimbursable expenses 205,799 202,348 194,358 205,240 Gross profit 70,203 64,981 59,847 71,540 Operating income (loss) 14,149 (200,575 ) 6,098 (27,128 ) Net income (loss) from continuing operations 5,155 (150,482 ) 4,132 (29,310 ) Income (loss) from discontinued operations, net of tax 143 309 238 (302 ) Net income (loss) 5,298 (150,173 ) 4,370 (29,612 ) Net earnings (loss) per basic share: Net income (loss) from continuing operations $ 0.24 $ (7.00 ) $ 0.19 $ (1.36 ) Income (loss) from discontinued operations, net of tax 0.01 0.01 0.01 (0.02 ) Net income (loss) $ 0.25 $ (6.99 ) $ 0.20 $ (1.38 ) Net earnings (loss) per diluted share: Net income (loss) from continuing operations $ 0.24 $ (7.00 ) $ 0.19 $ (1.36 ) Income (loss) from discontinued operations, net of tax 0.01 0.01 0.01 (0.02 ) Net income (loss) $ 0.25 $ (6.99 ) $ 0.20 $ (1.38 ) Weighted average shares used in calculating earnings per share: Basic 21,239 21,492 21,505 21,515 Diluted 21,474 21,492 21,622 21,515 Quarter Ended 2016 Mar. 31 Jun. 30 Sep. 30 Dec. 31 Revenues $ 180,489 $ 184,259 $ 183,400 $ 178,124 Reimbursable expenses 16,561 18,982 19,093 17,076 Total revenues and reimbursable expenses 197,050 203,241 202,493 195,200 Gross profit 65,180 77,138 71,131 60,090 Operating income 14,376 28,209 23,240 8,409 Net income from continuing operations 6,866 16,139 12,288 4,187 Income (loss) from discontinued operations, net of tax (864 ) (970 ) 4 (33 ) Net income 6,002 15,169 12,292 4,154 Net earnings per basic share: Net income from continuing operations $ 0.33 $ 0.77 $ 0.58 $ 0.20 Income (loss) from discontinued operations, net of tax (0.05 ) (0.05 ) — — Net income $ 0.28 $ 0.72 $ 0.58 $ 0.20 Net earnings per diluted share: Net income from continuing operations $ 0.32 $ 0.76 $ 0.57 $ 0.19 Income (loss) from discontinued operations, net of tax (0.04 ) (0.05 ) — — Net income $ 0.28 $ 0.71 $ 0.57 $ 0.19 Weighted average shares used in calculating earnings per share: Basic 21,114 21,061 21,076 21,083 Diluted 21,460 21,376 21,445 21,473

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block]	Intangible Assets Other Than Goodwill Identifiable intangible assets are amortized over their expected useful lives using a method that reflects the economic benefit expected to be derived from the assets or on a straight-line basis. We evaluate the recoverability of intangible assets periodically by taking into account events or circumstances that may warrant revised estimates of useful lives or that indicate the asset may be impaired.
Derivatives, Policy [Policy Text Block]	We recognize all derivative instruments as either assets or liabilities at fair value on the balance sheet. We have designated these derivative instruments as cash flow hedges. Therefore, changes in the fair value of the derivative instruments are recorded to other comprehensive income (“OCI”) to the extent effective and reclassified into interest expense upon settlement. The ineffective portion of the change in fair value of the derivative instruments is recognized in interest expense.
Basis of Presentation and Principles of Consolidation	The consolidated financial statements include the accounts of Huron Consulting Group Inc. and its subsidiaries, all of which are wholly-owned. All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and accompanying disclosures. Actual results may differ from these estimates and assumptions.
Revenue Recognition	Revenue Recognition Revenue is recognized when persuasive evidence of an arrangement exists, the related services are provided, the price is fixed or determinable, and collectability is reasonably assured. We generate the majority of our revenues from providing professional services under four types of billing arrangements: fixed-fee (including software license revenue), time-and-expense, performance-based, and software support and maintenance and subscriptions. In fixed-fee billing arrangements, we agree to a pre-established fee in exchange for a predetermined set of professional services. We set the fees based on our estimates of the costs and timing for completing the engagements. We generally recognize revenues under fixed-fee billing arrangements using a proportionate performance approach, which is based on work completed to-date versus our estimates of the total services to be provided under the engagement. Contracts within our Studer Group solution are fixed-fee partner contracts with multiple deliverables, which primarily consist of coaching services, as well as seminars, materials and software products (“Partner Contracts”). Revenues for coaching services and software products are generally recognized on a straight-line basis over the length of the contract. All other revenues under Partner Contracts are recognized at the time the service is provided. Estimates of total engagement revenues and cost of services are monitored regularly during the term of the engagement. If our estimates indicate a potential loss, such loss is recognized in the period in which the loss first becomes probable and reasonably estimable. We also generate revenues from software licenses for our revenue cycle management software and research administration and compliance software. Licenses for our revenue cycle management software are sold only as a component of our consulting projects, and the services we provide are essential to the functionality of the software. Therefore, revenues from these software licenses are recognized over the term of the related consulting services contract. License revenue from our research administration and compliance software is generally recognized in the month in which the software is delivered. Time-and-expense billing arrangements require the client to pay based on the number of hours worked by our revenue-generating professionals at agreed upon rates. Time-and-expense arrangements also include certain speaking engagements, conferences, and publication orders purchased by our clients outside of Partner Contracts within our Studer Group solution. We recognize revenues under time-and-expense arrangements as the related services or publications are provided. In performance-based billing arrangements, fees are tied to the attainment of contractually defined objectives. We enter into performance-based engagements in essentially two forms. First, we generally earn fees that are directly related to the savings formally acknowledged by the client as a result of adopting our recommendations for improving operational and cost effectiveness in the areas we review. Second, we have performance-based engagements in which we earn a success fee when and if certain predefined outcomes occur. We do not recognize revenues under performance-based billing arrangements until all related performance criteria are met. Clients that have purchased one of our software licenses can pay an annual fee for software support and maintenance. We also generate subscription revenue from our cloud-based analytic tools and solutions. Software support and maintenance and subscription-based revenues are recognized ratably over the support or subscription period, which ranges from one to three years. These fees are billed in advance and included in deferred revenues until recognized. We have arrangements with clients in which we provide multiple elements of services under one engagement contract. Revenues under these types of arrangements are allocated to each element based on the element’s fair value and recognized pursuant to the criteria described above. Provisions are recorded for the estimated realization adjustments on all engagements, including engagements for which fees are subject to review by the bankruptcy courts. Expense reimbursements that are billable to clients are included in total revenues and reimbursable expenses, and typically an equivalent amount of reimbursable expenses are included in total direct costs and reimbursable expenses. Reimbursable expenses are primarily recognized as revenue in the period in which the expense is incurred. Subcontractors that are billed to clients at cost are also included in reimbursable expenses. When billings do not specifically identify reimbursable expenses, we allocate the portion of the billings equivalent to these expenses to reimbursable expenses. Differences between the timing of billings and the recognition of revenue are recognized as either unbilled services or deferred revenues in the accompanying consolidated balance sheets. Revenues recognized for services performed but not yet billed to clients are recorded as unbilled services. Client prepayments and retainers are classified as deferred revenues and recognized over future periods as earned in accordance with the applicable engagement agreement.
Allowances for Doubtful Accounts and Unbilled Services	Allowances for Doubtful Accounts and Unbilled Services We maintain allowances for doubtful accounts and for services performed but not yet billed based on several factors, including the estimated cash realization from amounts due from clients, an assessment of a client’s ability to make required payments, and the historical percentages of fee adjustments and write-offs by age of receivables and unbilled services. The allowances are assessed by management on a regular basis. These estimates may differ from actual results. If the financial condition of a client deteriorates in the future, impacting the client’s ability to make payments, an increase to our allowance might be required or our allowance may not be sufficient to cover actual write-offs. We record the provision for doubtful accounts and unbilled services as a reduction in revenue to the extent the provision relates to fee adjustments and other discretionary pricing adjustments. To the extent the provision relates to a client’s inability to make required payments on accounts receivables, we record the provision to selling, general and administrative expenses.
Direct Costs and Reimbursable Expenses	Direct Costs and Reimbursable Expenses Direct costs and reimbursable expenses consist primarily of revenue-generating employee compensation and their related benefits and share-based compensation costs, as well as commissions, the cost of outside consultants or subcontractors assigned to revenue-generating activities, technology costs, other third-party costs directly attributable to our revenue-generating activities, and direct expenses to be reimbursed by clients. Direct costs and reimbursable expenses incurred on engagements are expensed in the period incurred.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly liquid investments, including overnight investments and commercial paper, with original maturities of three months or less to be cash equivalents.
Concentrations of Credit Risk	Concentrations of Credit Risk To the extent receivables from clients become delinquent, collection activities commence. No single client balance is considered large enough to pose a material credit risk. The allowances for doubtful accounts and unbilled services are based upon the expected ability to collect accounts receivable and bill and collect unbilled services. Management does not anticipate incurring losses on accounts receivable in excess of established allowances. See Note 18 “Segment Information” for concentration of accounts receivable and unbilled services. We hold our cash in accounts at multiple third-party financial institutions. These deposits, at times, may exceed federally insured limits. We review the credit ratings of these financial institutions, regularly monitor the cash balances in these accounts, and adjust the balances as appropriate. However, these cash balances could be impacted if the underlying financial institutions fail or are subject to other adverse conditions in the financial markets.
Investments	Long-term Investment Our long-term investment consists of our convertible debt investment in Shorelight Holdings, LLC. We classified the investment as available-for-sale at the time of purchase and reevaluate such classification as of each balance sheet date. The investment is carried at fair value with unrealized holding gains and losses reported in other comprehensive income. If the investment is in an unrealized loss position, we assess whether the investment is other than temporarily impaired. We consider impairments to be other than temporary if they are related to significant credit deterioration or if it is likely we will sell the security before the recovery of its cost basis. We have not identified any other than temporary impairments for our convertible debt investment. In the event there are realized gains and losses or declines in value judged to be other than temporary, we will record the amount in earnings. See Note 12 “Fair Value of Financial Instruments” for further information on our convertible debt investment.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost, less accumulated depreciation. Depreciation of property and equipment is computed on a straight-line basis over the estimated useful lives of the assets. Software, computers, and related equipment are depreciated over an estimated useful life of two to four years. Furniture and fixtures are depreciated over five years. Aircraft are depreciated over ten years. Leasehold improvements are amortized over the lesser of the estimated useful life of the asset or the initial term of the lease.
Software Development Costs	Software Development Costs We incur internal and external software development costs related to our cloud computing applications and software for internal use. We capitalize these software development costs incurred during the application development stage. Costs related to preliminary project activities and post implementation activities are expensed as incurred. Once the project is substantially complete and ready for its intended use these costs are amortized on a straight-line basis over the technology's estimated useful life. Acquired technology assets are initially recorded at fair value and amortized on a straight-line basis over the estimated useful life. We also incur internal and external software development costs related to our software products that will be sold, leased, or otherwise marketed. We expense these software development costs until technological feasibility has been established. Thereafter and until the software is available for general release to customers, these software development costs are capitalized and subsequently reported at the lower of unamortized cost or net realizable value. These capitalized development costs are amortized in proportion to current and future revenue for each product with an annual minimum equal to the straight-line amortization over the remaining estimated economic life of the product. We classify capitalized software development costs as other non-current assets on our consolidated balance sheet.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets, including property and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Events relating to recoverability may include significant unfavorable changes in business conditions, recurring losses, or a significant decline in forecasted operating results over an extended period of time. We evaluate the recoverability of long-lived assets based on forecasted undiscounted cash flows.
Goodwill	Goodwill For acquisitions accounted for as a business combination, goodwill represents the excess of the cost over the fair value of the net assets acquired. We are required to test goodwill for impairment, at the reporting unit level, annually and when events or circumstances indicate the fair value of a reporting unit may be below its carrying value. A reporting unit is an operating segment or one level below an operating segment (referred to as a component) to which goodwill is assigned when initially recorded. We assign goodwill to reporting units based on our integration plans and the expected synergies resulting from the acquisition. We have six reporting units: Healthcare, Education, Business Advisory, Enterprise Solutions and Analytics, Strategy and Innovation, and Life Sciences. The Business Advisory, Enterprise Solutions and Analytics, Strategy and Innovation, and Life Sciences reporting units make up our Business Advisory operating segment. We test goodwill for impairment annually and whenever events or circumstances make it more likely than not that an impairment may have occurred. We perform our annual goodwill impairment test as of November 30 and monitor for interim triggering events on an ongoing basis.
Business Combinations	Business Combinations We use the acquisition method of accounting for business combinations . Each acquired company’s operating results are included in our consolidated financial statements starting on the date of acquisition. The purchase price is equivalent to the fair value of consideration transferred. Tangible and identifiable intangible assets acquired and liabilities assumed are recorded at fair value as of the acquisition date. Goodwill is recognized for the excess of purchase price over the net fair value of tangible and intangible assets acquired and liabilities assumed. Contingent consideration, which is primarily based on the business achieving certain performance targets, is recognized at its fair value on the acquisition date, and changes in fair value are recognized in earnings until settled.
Deferred Lease Incentives	Deferred Lease Incentives We record the portion of the deferred lease incentive liability that we expect to recognize over a period greater than one year as a non-current liability. The non-current portion of the deferred lease incentive liability totaled $15.3 million and $10.7 million at December 31, 2017 and 2016 , respectively, and was primarily generated from tenant improvement allowances and rent abatement. Deferred lease incentives are amortized on a straight-line basis over the life of the lease. The portion of the deferred lease incentive corresponding to the rent payments that will be paid within 12 months of the balance sheet date is classified as a current liability. We monitor the classification of such liabilities based on the expectation of their utilization periods.
Income Taxes	Income Taxes Current tax liabilities and assets are recognized for the estimated taxes payable or refundable, respectively, on the tax returns for the current year. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. To the extent that deferred tax assets will not likely be recovered from future taxable income, a valuation allowance is established against such deferred tax assets.
Share-Based Compensation	Share-Based Compensation Share-based compensation cost is measured based on the grant date fair value of the respective awards. We generally recognize share-based compensation ratably using the straight-line attribution method; however, for those awards with performance criteria and graded vesting features, we use the graded vesting attribution method. It is our policy to account for forfeitures as they occur.
Sponsorship and Advertising Costs	Sponsorship and Advertising Costs Sponsorship and advertising costs are expensed as incurred.
Debt Issuance Costs	We have separated the Convertible Notes into liability and equity components. The carrying amount of the liability component was determined by measuring the fair value of a similar liability that does not have an associated convertible feature. The carrying value of the equity component representing the conversion option, which is recognized as a debt discount, was determined by deducting the fair value of the liability component from the proceeds of the Convertible Notes. The debt discount is amortized to interest expense using the effective interest method over the term of the Convertible Notes. The equity component will not be remeasured as long as it continues to meet the conditions for equity classification. Refer to Note 7 “Financing Arrangements” for further information regarding the Convertible Notes. Debt Issuance Costs We amortize the costs we incur to obtain debt financing over the contractual life of the related debt using the effective interest method for non-revolving debt and the straight-line method for revolving debt. The amortization expense is included in interest expense, net of interest income in our statement of earnings. Unamortized debt issuance costs attributable to our revolving credit facility are included as a component of other non-current assets. Unamortized debt issuance costs attributable to our Convertible Notes are recorded as a deduction from the carrying amount of the debt liability.
Foreign Currency	Foreign Currency Assets and liabilities of foreign subsidiaries whose functional currency is not the United States Dollar (USD) are translated into the USD using the exchange rates in effect at period end. Revenue and expense items are translated using the average exchange rates for the period. Foreign currency translation adjustments are included in accumulated other comprehensive income, which is a component of stockholders’ equity. Foreign currency transaction gains and losses are included in other income, net on the statement of earnings.
Segment Reporting	Segment Reporting Segments are defined as components of a company that engage in business activities from which they may earn revenues and incur expenses, and for which separate financial information is available and is evaluated regularly by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. Our chief operating decision maker manages the business under three operating segments, which are reportable segments: Healthcare, Education, and Business Advisory. During the second quarter of 2017, we reorganized our internal financial reporting structure, which management uses to assess performance and allocate resources, by moving our Life Sciences practice from the Education and Life Sciences segment to the Business Advisory segment. The remaining Education and Life Sciences segment is now referred to as the Education segment. While our consolidated results have not been impacted, we have reclassified our historical segment information for consistent presentation.
New Accounting Pronouncements	New Accounting Pronouncements Recently Adopted In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income . ASU 2018-02 allows entities to reclassify stranded tax effects resulting from the enactment of the 2017 Tax Cuts and Jobs Act ("2017 Tax Reform") from accumulated other comprehensive income to retained earnings. We adopted ASU 2018-02 upon issuance and reclassified $0.5 million of stranded tax effects, primarily related to our convertible debt investment, from accumulated other comprehensive income to retained earnings as of December 31, 2017. Refer to Note 16 "Income Taxes" for additional information on the 2017 Tax Reform. In January 2017, the FASB issued ASU 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment . ASU 2017-04 eliminates Step 2 of the goodwill impairment test, which required us to determine the implied fair value of goodwill by allocating the reporting unit's fair value to each of its assets and liabilities as if the reporting unit was acquired in a business acquisition. Instead, the updated guidance requires an entity to perform its annual or interim goodwill impairment test by comparing the fair value of the reporting unit to its carrying value, and recognizing a non-cash impairment charge for the amount by which the carrying value exceeds the reporting unit's fair value with the loss not exceeding the total amount of goodwill allocated to that reporting unit. We adopted this ASU in the second quarter of 2017 on a prospective basis and applied the new guidance to our interim goodwill impairment tests performed in the second quarter of 2017 and our annual impairment test performed as of November 30, 2017. Refer to Note 5 “Goodwill and Intangible Assets” for additional information on our interim and annual goodwill impairment tests performed. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting . ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the accounting for income taxes, classification of excess tax benefits on the statement of cash flows, and forfeitures. We adopted this guidance in the first quarter of 2017, at which time we began recognizing excess tax benefits and deficiencies as income tax benefit or expense in our consolidated statements of operations on a prospective basis. We recognized $1.8 million of net excess tax deficiencies as income tax expense in our consolidated statement of operations for the year ended December 31, 2017 . Additionally, upon adoption, we began classifying excess tax benefits as an operating activity on the statement of cash flows on a retrospective basis. As a result, we reclassified $0.9 million and $3.6 million of excess tax benefits for the years ended December 31, 2016 and 2015 , respectively, from cash flows from financing activities to cash flows from operating activities on our statement of cash flows. We elected to account for share-based award forfeitures as they occur, and applied this accounting change on a modified retrospective basis as a cumulative-effect adjustment to retained earnings of $0.4 million during the first quarter of 2017. In March 2016, the FASB issued ASU 2016-06, Derivatives and Hedging: Contingent Put and Call Options in Debt Instruments . ASU 2016-06 clarifies that in assessing whether an embedded contingent put or call option is clearly and closely related to the debt host, an entity is required to perform only the four-step decision sequence in ASC 815-15-25-42 (as amended by the ASU). The entity does not have to separately assess whether the event that triggers its ability to exercise the contingent option is itself indexed only to interest rates or credit risk. We adopted these amendments in the first quarter of 2017 on a modified retrospective basis. The adoption of these amendments did not have any impact on our consolidated financial statements. Not Yet Adopted In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities . The amendments to the guidance improve and simplify accounting rules for hedge accounting to better present the economic results of an entity’s risk management activities in its financial statements and improve the disclosures of hedging arrangements. Additionally, ASU 2017-12 simplifies the hedge documentation and effectiveness assessment requirements. The updated guidance is effective for us beginning January 1, 2019. We do not expect this guidance to have a material impact on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-02, Leases , which supersedes ASC Topic 840, Leases , and sets forth the principles for the recognition, measurement, presentation, and disclosure of leases for both lessees and lessors. ASU 2016-02 requires lessees to classify leases as either finance or operating leases and to record on the balance sheet a right-of-use asset and a lease liability, equal to the present value of the remaining lease payments, for all leases with a term greater than 12 months regardless of the lease classification. The lease classification will determine whether the lease expense is recognized based on an effective interest rate method or a straight-line basis over the term of the lease. ASU 2016-02 will be effective for us beginning January 1, 2019, with early adoption permitted. Entities are required to use a modified retrospective transition method for existing leases. We are currently evaluating the potential impact this guidance will have on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . The amendments to the guidance enhance the reporting model for financial instruments, which includes amendments to address aspects of recognition, measurement, presentation, and disclosure. The updated guidance is effective for us beginning January 1, 2018. We do not expect this guidance to have a material impact on our consolidated financial statements. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, as a new Topic , ASC 606. The new revenue recognition standard provides a five-step analysis of transactions to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In accordance with the new standard, we will adopt ASU 2014-09 on January 1, 2018 using the modified retrospective transition method, under which the new guidance will be applied to the current period presented in the financial statements and a cumulative-effect adjustment will be recorded as of the date of adoption. We are currently completing our analysis to determine the impact of ASC 606 on our consolidated financial statements, and expect the more impactful aspect of ASC 606 will relate to how we recognize revenue under performance-based fee billing arrangements. Currently, we recognize revenue under these arrangements once all related performance criteria are met and the amount to be recognized is fixed or determinable. However, upon adoption of the new standard, we will estimate these amounts and recognize the estimated amounts as services are performed over the contractual term of the engagements. The cumulative-effect adjustment will capture the amount of revenue we would have recognized on all outstanding performance-based fee billing arrangements under ASC 606 as of the adoption date, and record the difference as a cumulative-effect adjustment to retained earnings. Further, ASC 606 provides for certain practical expedients that we intend to use, including the option to expense contract acquisition costs as incurred if the contract term is one year or shorter. We also intend to use the as-invoiced practical expedient, which permits us to recognize revenue in the amount to which we have the right to invoice a customer if that amount corresponds to the value of the performance completed to date.

Fair Value of Financial Instr28

Fair Value of Financial Instruments - (Policies)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair value measurement policy	Certain of our assets and liabilities are measured at fair value. Fair value is defined as the price that would be received to sell an asset or the price that would be paid to transfer a liability in an orderly transaction between market participants at the measurement date. GAAP establishes a fair value hierarchy for inputs used in measuring fair value and requires companies to maximize the use of observable inputs and minimize the use of unobservable inputs. The fair value hierarchy consists of three levels based on the objectivity of the inputs as follows: Level 1 Inputs Quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 Inputs Quoted prices in active markets for similar assets or liabilities; quoted prices for identical or similar assets or liabilities in markets that are not active; inputs other than quoted prices that are observable for the asset or liability; or inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3 Inputs Unobservable inputs for the asset or liability, and include situations in which there is little, if any, market activity for the asset or liability.

Income Taxes - (Policies)

Income Taxes - (Policies)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	We recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position are measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate resolution.

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2015
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures	The table below summarizes the operating results of Huron Legal for the year ended December 31, 2015. Year Ended Revenues and reimbursable expenses: Revenues $ 139,430 Reimbursable expenses 3,148 Total revenues and reimbursable expenses 142,578 Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses): Direct costs 95,247 Amortization of intangible assets and software development costs 233 Reimbursable expenses 3,153 Total direct costs and reimbursable expenses 98,633 Operating expenses and other operating gain: Selling, general and administrative expenses 20,640 Restructuring charges (1) 13,341 Other gain (900 ) Depreciation and amortization 9,605 Total operating expenses and other operating gain 42,686 Operating income 1,259 Other expense, net (13 ) Income from discontinued operations before taxes 1,246 Loss on disposal (2,303 ) Total loss from discontinued operations before taxes (1,057 ) Income tax benefit (2) 1,786 Net loss from discontinued operations $ (2,843 ) (1) During 2015, the Huron Legal segment incurred a $13.3 million restructuring charge. Of the $13.3 million , $6.1 million related to accelerated depreciation on assets disposed of as a result of the sale, $5.1 million related to employee costs incurred in connection with the sale, $1.1 million related to the accrual of our remaining lease obligations for vacated spaces, net of estimated sublease income, and $1.0 million related to severance costs incurred from prior workforce reductions. (2) Refer to Note 16 "Income Taxes" for additional detail on the income tax benefit recognized for discontinued operations. The table below summarizes the amounts reflected in our consolidated statements of cash flows that relate to the discontinued operations for the year ended December 31, 2015. Year Ended Depreciation and amortization $ 15,974 Share-based compensation $ 2,215 Purchases of property and equipment $ 6,234 Significant non-cash investing items of discontinued operations: Contingent consideration related to a business acquisition $ 900

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2017
Innosight Holdings, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Summary of Fair Value of Consideration Transferred	The acquisition date fair value of the consideration transferred for Innosight was $113.6 million , which consisted of the following: Fair value of consideration transferred Cash $ 90,725 Common stock 9,560 Contingent consideration liability 12,050 Net working capital adjustment 1,272 Total consideration transferred $ 113,607
Preliminary Allocation of the Purchase Price to the Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the preliminary allocation of the purchase price to the fair value of assets acquired and liabilities assumed as of the acquisition date. March 1, 2017 Assets acquired: Accounts receivable $ 7,752 Unbilled services 1,881 Prepaid expenses and other current assets 468 Property and equipment 419 Intangible assets 18,015 Liabilities assumed: Accounts payable 531 Accrued expenses and other current liabilities 894 Accrued payroll and related benefits 883 Deferred revenues 30 Total identifiable net assets 26,197 Goodwill 87,410 Total purchase price $ 113,607
Schedule of Components of Identifiable Intangible Assets Acquired and their Estimated Useful Lives	The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the acquisition date. Fair Value Useful Life in Years Customer relationships $ 9,500 6 Trade name 6,000 6 Customer contracts 1,000 1 Non-compete agreements 1,300 5 Favorable lease contract 215 1 Total intangible assets subject to amortization $ 18,015
Summary of Supplemental Pro Forma Consolidated Results of Operations	The following unaudited supplemental pro forma information summarizes the combined results of operations of Huron and Innosight as though the companies were combined on January 1, 2016. Year Ended December 31, 2017 2016 Revenues $ 741,695 $ 769,114 Net income (loss) from continuing operations $ (167,346 ) $ 42,760 Net income (loss) from continuing operations per share - basic $ (7.79 ) $ 2.01 Net income (loss) from continuing operations per share - diluted $ (7.79 ) $ 1.98
Studer Group
Acquired Finite-Lived Intangible Assets [Line Items]
Summary of Fair Value of Consideration Transferred	The acquisition date fair value of the consideration transferred for Studer Group was approximately $325.2 million , which consisted of the following: Fair value of consideration transferred Cash $ 323,237 Common stock 2,204 Net working capital adjustment (255 ) Total consideration transferred $ 325,186
Preliminary Allocation of the Purchase Price to the Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the allocation of the purchase price to the fair value of assets acquired and liabilities assumed as of the acquisition date. February 12, 2015 Assets acquired: Accounts receivable $ 14,906 Prepaid expenses and other current assets 1,385 Deferred income tax asset 4,335 Property and equipment 4,509 Intangible assets 97,500 Liabilities assumed: Accounts payable 760 Accrued expenses and other current liabilities 2,868 Accrued payroll and related benefits 1,574 Deferred revenues 2,449 Deferred income tax liability 21,263 Other non-current liabilities 1,211 Total identifiable net assets 92,510 Goodwill 232,676 Total purchase price $ 325,186
Schedule of Components of Identifiable Intangible Assets Acquired and their Estimated Useful Lives	The following table sets forth the components of identifiable intangible assets acquired and their estimated useful lives as of the acquisition date. Fair Value Useful Life in Years Customer relationships $ 42,400 9 Customer contracts 25,100 4 Trade name 22,800 5 Technology and software 3,900 3 Publishing content 3,300 3 Total intangible assets subject to amortization $ 97,500
Summary of Supplemental Pro Forma Consolidated Results of Operations	The following unaudited supplemental pro forma information summarizes the combined results of operations for Huron and Studer Group for the twelve months ended December 31, 2015 as though the companies were combined on January 1, 2014. Year Ended December 31, 2015 Revenues $ 709,813 Net income from continuing operations $ 63,600 Net income from continuing operations per share - basic $ 2.87 Net income from continuing operations per share - diluted $ 2.81

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	The table below sets forth the changes in the carrying amount of goodwill by reportable segment for the years ended December 31, 2017 and 2016 . Healthcare Education Business Advisory Total Balance as of December 31, 2015: Goodwill $ 610,264 $ 102,906 $ 181,213 $ 894,383 Accumulated impairment losses — — (142,983 ) (142,983 ) Goodwill, net as of December 31, 2015 $ 610,264 $ 102,906 $ 38,230 $ 751,400 Goodwill recorded in connection with business combinations (1) 26,538 — 21,824 48,362 Foreign currency translation — — 100 100 Balance as of December 31, 2016: Goodwill 636,802 102,906 203,137 942,845 Accumulated impairment losses — — (142,983 ) (142,983 ) Goodwill, net as of December 31, 2016 $ 636,802 $ 102,906 $ 60,154 $ 799,862 Goodwill recorded in connection with business combinations (1) 8 10,252 88,183 98,443 Goodwill impairment charge (208,081 ) — (45,012 ) (253,093 ) Goodwill reallocation (2) — (10,794 ) 10,794 — Goodwill allocated to disposal of business (3) — — (568 ) (568 ) Foreign currency translation — 465 641 1,106 Balance as of December 31, 2017: Goodwill 636,810 102,829 302,187 1,041,826 Accumulated impairment losses (208,081 ) — (187,995 ) (396,076 ) Goodwill, net as of December 31, 2017: $ 428,729 $ 102,829 $ 114,192 $ 645,750 (1) Refer to Note 4 "Acquisitions" for additional information on the goodwill recorded in connection with business combinations. (2) In the second quarter of 2017, we reorganized our internal financial reporting structure, which management uses to assess performance and allocate resources, by moving our Life Sciences practice from the Education and Life Sciences segment to the Business Advisory segment. The remaining Education and Life Sciences segment is now referred to as the Education segment. The Life Sciences practice is a separate reporting unit for purposes of goodwill impairment testing. See Note 18 "Segment Information" for additional information on our reportable segments. (3) On June 16, 2017, we sold our Life Sciences Compliance and Operations practice ("Life Sciences C&O") to a third-party, and allocated a portion of goodwill within the Life Sciences reporting unit to the disposed business based on the relative fair values of Life Sciences C&O and the remaining reporting unit. The allocated goodwill of $0.6 million was written off and included in the gain on sale of Life Sciences C&O. The sale of Life Sciences C&O did not meet the criteria for reporting separately as discontinued operations. In connection with the sale, we recorded a $0.9 million gain which is included in other income, net in our consolidated statements of operations.
Intangible Assets	Intangible assets as of December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Useful Life in Years Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated Amortization Customer relationships 4 to 13 $ 106,195 $ 51,588 $ 89,279 $ 34,827 Trade names 2 to 6 29,016 18,915 22,930 11,652 Customer contracts 1 to 4 25,154 24,751 26,497 21,295 Technology and software 3 to 5 9,340 5,098 8,970 2,667 Non-competition agreements 3 to 5 5,163 2,637 3,685 1,697 Publishing content 3 3,300 3,163 3,300 2,062 Favorable lease contract 3 720 425 720 203 In-process technology Indefinite — — 370 — Total $ 178,888 $ 106,577 $ 155,751 $ 74,403
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The table below sets forth the estimated annual amortization expense for each of the five succeeding years for the intangible assets recorded as of December 31, 2017 . Year Ending December 31, Estimated Amortization Expense 2018 $ 23,936 2019 $ 17,279 2020 $ 12,116 2021 $ 8,070 2022 $ 6,092

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment	Property and equipment, net at December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Computers, related equipment, and software $ 46,216 $ 48,607 Leasehold improvements 45,244 38,502 Furniture and fixtures 16,434 12,545 Aircraft 7,541 — Assets under construction 250 294 Property and equipment 115,685 99,948 Accumulated depreciation and amortization (70,144 ) (67,514 ) Property and equipment, net $ 45,541 $ 32,434

Financing Arrangements (Tables)

Financing Arrangements (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Summary of Carrying Amounts of Debt	A summary of the carrying amounts of our debt follows: As of December 31, 2017 2016 1.25% convertible senior notes due 2019 $ 233,140 $ 224,065 Senior secured credit facility 105,000 68,000 Promissory note due 2024 4,868 — Total long-term debt $ 343,008 $ 292,065 Current maturities of debt (1) (501 ) — Long-term debt, net of current portion $ 342,507 $ 292,065
Schedule of Maturities of Long-term Debt	of the scheduled remaining principal payments of our debt as of December 31, 2017 . Principal Payments of Long-Term Debt 2018 $ 501 2019 $ 250,515 2020 $ 105,529 2021 $ 544 2022 $ 559 Thereafter $ 2,221
Schedule of Notes	As of December 31, 2017 and 2016 , the Convertible Notes consisted of the following: As of December 31, 2017 2016 Liability component: Proceeds $ 250,000 $ 250,000 Less: debt discount, net of amortization (14,668 ) (22,520 ) Less: debt issuance costs, net of amortization (2,192 ) (3,415 ) Net carrying amount $ 233,140 $ 224,065 Equity component (1) $ 39,287 $ 39,287 (1) Included in additional paid-in capital on the consolidated balance sheet.
Summary of Interest Expense Recognized	The following table presents the amount of interest expense recognized related to the Convertible Notes for the periods presented. Year Ended December 31, 2017 2016 2015 Contractual interest coupon $ 3,125 $ 3,125 $ 3,125 Amortization of debt discount 7,851 7,488 7,141 Amortization of debt issuance costs 1,224 1,201 1,180 Total interest expense $ 12,200 $ 11,814 $ 11,446

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Earnings Per Share	Basic earnings per share excludes dilution and is computed by dividing net income by the weighted average number of common shares outstanding for the period, excluding unvested restricted common stock. Diluted earnings per share reflects the potential reduction in earnings per share that could occur if securities or other contracts to issue common stock were exercised or converted into common stock under the treasury stock method. Such securities or other contracts include unvested restricted stock awards, outstanding common stock options, convertible senior notes, and outstanding warrants, to the extent dilutive. In periods for which we report a net loss from continuing operations, diluted weighted average common shares outstanding excludes all potential common stock equivalents as their impact on diluted net loss from continuing operations per share would be anti-dilutive. Earnings (loss) per share under the basic and diluted computations are as follows: Year Ended December 31, 2017 2016 2015 Net income (loss) from continuing operations $ (170,505 ) $ 39,480 $ 61,895 Income (loss) from discontinued operations, net of tax 388 (1,863 ) (2,843 ) Net income (loss) $ (170,117 ) $ 37,617 $ 59,052 Weighted average common shares outstanding—basic 21,439 21,084 22,136 Weighted average common stock equivalents — 340 464 Weighted average common shares outstanding—diluted 21,439 21,424 22,600 Net earnings (loss) per basic share: Net income (loss) from continuing operations $ (7.95 ) $ 1.87 $ 2.80 Income (loss) from discontinued operations, net of tax 0.02 (0.09 ) (0.13 ) Net income (loss) $ (7.93 ) $ 1.78 $ 2.67 Net earnings (loss) per diluted share: Net income (loss) from continuing operations $ (7.95 ) $ 1.84 $ 2.74 Income (loss) from discontinued operations, net of tax 0.02 (0.08 ) (0.13 ) Net income (loss) $ (7.93 ) $ 1.76 $ 2.61
Summary of Anti-dilutive Securities Excluded from Computation of Weighted Average Common Stock Equivalents	The number of anti-dilutive securities excluded from the computation of the weighted average common stock equivalents presented above were as follows: As of December 31, 2017 2016 2015 Unvested restricted stock awards 636 2 21 Outstanding common stock options 194 — — Convertible senior notes 3,129 3,129 3,129 Warrants related to the issuance of convertible senior notes 3,129 3,129 3,129 Total anti-dilutive securities 7,088 6,260 6,279

Restructuring Charges - (Tables

Restructuring Charges - (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Reserve by Type of Cost	The table below sets forth the changes in the carrying amount of our restructuring charge liability by restructuring type for the years ended December 31, 2017 and 2016 . Employee Costs Office Space Reductions Other Total Balance as of December 31, 2015 $ 2,323 $ 6,379 $ — $ 8,702 Additions (1) 9,082 57 585 9,724 Payments (5,906 ) (2,424 ) (482 ) (8,812 ) Adjustments (1) (317 ) 1,765 245 1,693 Non-cash items — (4 ) (324 ) (328 ) Balance as of December 31, 2016 5,182 5,773 24 10,979 Additions (1) 3,859 2,426 110 6,395 Payments (7,611 ) (2,860 ) 5 (10,466 ) Adjustments (1) (117 ) (973 ) (78 ) (1,168 ) Non-cash items (46 ) (119 ) (61 ) (226 ) Balance as of December 31, 2017 $ 1,267 $ 4,247 $ — $ 5,514 (1) Additions and adjustments for the years ended December 31, 2017 and 2016 include a gain of $1.0 million and a charge of $2.0 million , respectively, related to updated lease assumptions for vacated offices spaces directly related to discontinued operations. Refer to Note 3 "Discontinued Operations" for additional information on our discontinued operations.

Derivative Instruments and He37

Derivative Instruments and Hedging Activity (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value Interest Rate Swaps Designated as Cash Flow Hedging Instruments	The table below sets forth additional information relating to our interest rate swaps designated as cash flow hedging instruments as of December 31, 2017 and 2016 . Fair Value (Derivative Asset and Liability) As of December 31, Balance Sheet Location 2017 2016 Other non-current assets $ 581 $ — Accrued expenses $ 48 $ 54

Fair Value of Financial Instr38

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The table below sets forth our fair value hierarchy for our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2017 and 2016 . Level 1 Level 2 Level 3 Total December 31, 2017 Assets: Interest rate swaps $ — $ 533 $ — $ 533 Promissory note — — 1,078 1,078 Convertible debt investment — — 39,904 39,904 Deferred compensation assets — 17,786 — 17,786 Total assets $ — $ 18,319 $ 40,982 $ 59,301 Liabilities: Contingent consideration for business acquisitions $ — $ — $ 22,828 $ 22,828 Total liabilities $ — $ — $ 22,828 $ 22,828 December 31, 2016 Assets: Promissory note $ — $ — $ 2,325 $ 2,325 Convertible debt investment — — 34,675 34,675 Deferred compensation assets — 16,408 — 16,408 Total assets $ — $ 16,408 $ 37,000 $ 53,408 Liabilities: Interest rate swaps $ — $ 54 $ — $ 54 Contingent consideration for business acquisitions — — 8,827 8,827 Total liabilities $ — $ 54 $ 8,827 $ 8,881
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block]	The carrying amount and estimated fair value of the Convertible Notes are as follows: December 31, 2017 December 31, 2016 Carrying Amount Estimated Fair Value Carrying Estimated 1.25% convertible senior notes due 2019 $ 233,140 $ 232,578 $ 224,065 $ 245,018
Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The table below sets forth the changes in the balance of the promissory note for the years ended December 31, 2017 and 2016 . Promissory Note Balance as of December 31, 2015 $ 2,309 Interest payments received (191 ) Change in fair value of promissory note 207 Balance as of December 31, 2016 2,325 Interest payments received (185 ) Principal payments received (1,177 ) Change in fair value of promissory note 115 Balance as of December 31, 2017 $ 1,078
Convertible Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The table below sets forth the changes in the balance of the convertible debt investment for the years ended December 31, 2017 and 2016 . Convertible Debt Investment Balance as of December 31, 2015 $ 34,831 Change in fair value of convertible debt investment (156 ) Balance as of December 31, 2016 34,675 Change in fair value of convertible debt investment 5,229 Balance as of December 31, 2017 $ 39,904
Contingent Consideration Liability [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The table below sets forth the changes in the balance of the contingent consideration for business acquisitions for the years ended December 31, 2017 and 2016 . Contingent Consideration for Business Acquisitions Balance as of December 31, 2015 $ 2,063 Acquisitions 8,754 Remeasurement of contingent consideration for business acquisitions (1,990 ) Balance as of December 31, 2016 8,827 Acquisitions 15,489 Payments (2,938 ) Remeasurement of contingent consideration for business acquisitions 1,111 Unrealized loss due to foreign currency translation 339 Balance as of December 31, 2017 $ 22,828

Other Comprehensive Income (L39

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Components of Accumulated Other Comprehensive Loss, Net of Tax	The table below sets forth the components of accumulated other comprehensive income (loss), net of tax for the years ended December 31, 2017 , 2016 , and 2015 . Foreign Currency Translation Available-for- Sale Investments Cash Flow Hedges (1) Total Balance as of December 31, 2014 $ (2,334 ) $ (250 ) $ (71 ) $ (2,655 ) Foreign currency translation adjustment, net of tax of $0 (403 ) — — (403 ) Reclassification adjustment into earnings, net of tax of $0 (2) 2,220 — — 2,220 Unrealized gain on investments, net of tax of $(2,709) — 4,435 — 4,435 Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $327 — — (492 ) (492 ) Reclassification adjustment into earnings, net of tax of $(320) — — 480 480 Balance as of December 31, 2015 (517 ) 4,185 (83 ) 3,585 Foreign currency translation adjustment, net of tax of $0 64 — — 64 Unrealized loss on investments, net of tax of $59 — (97 ) — (97 ) Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $122 — — (179 ) (179 ) Reclassification adjustment into earnings, net of tax of $(161) — — 242 242 Balance as of December 31, 2016 (453 ) 4,088 (20 ) 3,615 Foreign currency translation adjustment, net of tax of $0 1,602 — — 1,602 Unrealized gain on investments: Change in fair value, net of tax of $(998) — 4,231 — 4,231 Reclassification adjustment into retained earnings (3) — 493 — 493 Unrealized gain (loss) on cash flow hedges: Change in fair value, net of tax of $(106) — — 366 366 Reclassification adjustment into earnings, net of tax of $(46) — — 69 69 Reclassification adjustment into retained earnings (3) — — (6 ) (6 ) Balance as of December 31, 2017 $ 1,149 $ 8,812 $ 409 $ 10,370 (1) The before tax amounts reclassified from accumulated other comprehensive income (loss) related to our cash flow hedges are recorded to interest expense, net of interest income. (2) In connection with the divestiture of Huron Legal, which included the sale of certain wholly-owned foreign subsidiaries, we reclassified $2.2 million of accumulated translation losses to net income from discontinued operations. (3) Upon adoption of ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, we reclassified $0.5 million of stranded tax effects, which resulted from the enactment of the 2017 Tax Reform, from accumulated other comprehensive income to retained earnings. Refer to Note 2 "Summary of Significant Accounting Policies" for additional information on the adoption of ASU 2018-02.

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Restricted Stock Activity	The table below summarizes the restricted stock activity for the year ended December 31, 2017 . Number of Shares Weighted Average Grant Date Fair Value (in dollars) 2012 Omnibus Incentive Plan Stock Ownership Participation Program Total Nonvested restricted stock at December 31, 2016 610 12 622 $ 59.77 Granted 270 14 284 $ 42.11 Vested (247 ) (9 ) (256 ) $ 57.80 Forfeited (72 ) (4 ) (76 ) $ 59.18 Nonvested restricted stock at December 31, 2017 561 13 574 $ 51.97
Schedule of Performance-Based Stock Activity	The table below summarizes the performance-based stock activity for the year ended December 31, 2017 . All nonvested performance-based stock outstanding at December 31, 2016 and 2017 was granted under the 2012 Omnibus Incentive Plan. Number of Shares Weighted Average Grant Date Fair Value (in dollars) Nonvested performance-based stock at December 31, 2016 239 $ 58.47 Granted (1) 328 $ 42.75 Vested (85 ) $ 61.66 Forfeited (2) (129 ) $ 54.85 Nonvested performance-based stock at December 31, 2017 (3) 353 $ 44.45 (1) Shares granted in 2017 are presented at the stated target, which represents the base number of shares that could be earned. Actual shares earned may be below or, for certain grants, above the target based on the achievement of specific financial goals. (2) Forfeited shares include shares forfeited as a result of not meeting the performance criteria of the award as well as shares forfeited upon termination. (3) Of the 353,000 nonvested performance-based shares outstanding as of December 31, 2017 , approximately 316,000 shares were unearned and subject to achievement of specific financial goals. Once earned, the awards will be subject to time-based vesting according to the terms of the award. Based on 2017 financial results, approximately 235,000 of the 316,000 unearned shares will be forfeited in the first quarter of 2018 .
Schedule of Stock Option Activity	Stock option activity for the year ended December 31, 2017 was as follows: Number of Options (in thousands) Weighted Average Exercise Price (in dollars) Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2016 194 $ 29.06 4.3 $ 4.2 Granted — Exercised — Forfeited or expired — Outstanding at December 31, 2017 (1) 194 $ 29.06 3.3 $ 2.2 Exercisable at December 31, 2017 194 $ 29.06 3.3 $ 2.2 (1) Of the 194,000 outstanding options, approximately 157,000 were granted under the 2004 Omnibus Stock Plan, and the remaining 37,000 options were granted under the 2012 Omnibus Incentive Plan.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Tax Expense for Continuing Operations	The income tax expense for continuing operations for the years ended December 31, 2017 , 2016 , and 2015 consists of the following: Year Ended December 31, 2017 2016 2015 Current: Federal $ (635 ) $ 15,726 $ 4,806 State 545 1,623 2,380 Foreign 2,040 1,021 350 Total current 1,950 18,370 7,536 Deferred: Federal (46,103 ) 1,662 12,450 State (6,576 ) (274 ) 1,482 Foreign (1,270 ) (81 ) 202 Total deferred (53,949 ) 1,307 14,134 Income tax expense for continuing operations $ (51,999 ) $ 19,677 $ 21,670
Components of Income from Continuing Operations Before Income Tax Expense	The components of income from continuing operations before taxes were as follows: Year Ended December 31, 2017 2016 2015 U.S. $ (221,137 ) $ 56,141 $ 85,164 Foreign (1,367 ) 3,016 (1,599 ) Total $ (222,504 ) $ 59,157 $ 83,565
Reconciliation of Statutory Income Tax Rate to Our Effective Tax Rate for Continuing Operations	A reconciliation of the U.S. statutory income tax rate to our effective tax rate for continuing operations is as follows: Year Ended December 31, 2017 2016 2015 Percent of pretax income from continuing operations: At U.S. statutory tax rate 35.0 % 35.0 % 35.0 % State income taxes, net of federal benefit 2.7 1.7 4.6 Goodwill impairment charges (10.2 ) — — U.S. federal rate change (3.4 ) — — Transition tax on accumulated foreign earnings, net of credits (0.3 ) — — Stock-based compensation (0.8 ) — — Meals and entertainment (0.3 ) 1.1 0.6 Valuation allowance (0.2 ) (3.2 ) 0.5 Foreign source income 0.1 (0.5 ) 0.5 Tax credits / Section 199 Deduction 0.2 (1.1 ) (1.0 ) Net tax benefit related to “check-the-box” election (1) 1.2 — (14.7 ) Other (0.6 ) 0.3 0.4 Effective income tax rate for continuing operations 23.4 % 33.3 % 25.9 % (1) In the fourth quarter of 2015, we made a tax election to classify two of our wholly-owned foreign subsidiaries as disregarded entities for U.S. federal income tax purposes (commonly referred to as a “check-the-box” election). As a result of this election, we realized an income tax benefit of $13.0 million , of which $0.7 million is unrecognized, resulting in a net recognized tax benefit of $12.3 million . Due to the expiration of statute of limitations, in the third quarter of 2017, we recognized a $2.7 million tax benefit, including the reversal of accrued interest and penalties, related to a previously unrecognized tax benefit from our "check-the-box" election made in 2014 to treat one of our wholly-owned foreign subsidiaries as a disregarded entity for U.S federal income tax purposes.
Net Deferred Tax Liabilities for Continuing Operations	The net deferred tax liabilities for continuing operations at December 31, 2017 and 2016 consisted of the following: As of December 31, 2017 2016 Deferred tax assets: Share-based compensation $ 5,674 $ 10,151 Accrued payroll and other liabilities 7,010 10,004 Intangibles and goodwill 2,137 — Deferred lease incentives 4,352 4,666 Convertible note hedge transactions 250 12,197 Revenue recognition 1,586 1,983 Restructuring charge liability 1,104 2,230 Net operating loss carry-forwards 495 92 Tax credits 1,918 1,804 Other 882 1,934 Total deferred tax assets 25,408 45,061 Valuation allowance (1,247 ) (626 ) Net deferred tax assets 24,161 44,435 Deferred tax liabilities: Prepaid expenses (1,229 ) (2,500 ) Property and equipment (4,031 ) (2,933 ) Intangibles and goodwill — (60,411 ) Convertible note discount (3 ) (11,586 ) Convertible debt investment (3,110 ) (2,600 ) Other (133 ) (38 ) Total deferred tax liabilities (8,506 ) (80,068 ) Net deferred tax asset (liability) for continuing operations $ 15,655 $ (35,633 )
Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	A reconciliation of our beginning and ending amount of unrecognized tax benefits is as follows: Unrecognized Tax Benefits Balance at January 1, 2015 $ 2,488 Additions based on tax positions related to the current year 735 Balance at December 31, 2015 3,223 Additions based on tax positions related to the current year 117 Balance at December 31, 2016 3,340 Decrease due to lapse of statute of limitations (2,410 ) Decrease based on tax positions related to the prior year (117 ) Balance at December 31, 2017 $ 813

Commitments, Contingencies an42

Commitments, Contingencies and Guarantees (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Rental Commitments Under Non-Cancelable Leases and Sublease Income	Future minimum rental commitments under non-cancelable leases and sublease income as of December 31, 2017 , are as follows: Operating Lease Obligations Sublease Income 2018 $ 14,739 $ 1,316 2019 13,444 291 2020 12,266 — 2021 11,298 — 2022 10,409 — Thereafter 37,804 — Total $ 99,960 $ 1,607

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Components of Segment Information	The tables below set forth information about our operating segments for the years ended December 31, 2017 , 2016 , and 2015 , along with the items necessary to reconcile the segment information to the totals reported in the accompanying consolidated financial statements. We do not present financial information by geographic area because our international operations are immaterial. Year Ended December 31, 2017 2016 2015 Healthcare: Revenues $ 356,909 $ 424,912 $ 446,887 Operating income $ 118,761 $ 147,903 $ 169,560 Segment operating income as a percentage of segment revenues 33.3 % 34.8 % 37.9 % Education: Revenues $ 167,908 $ 149,817 $ 134,009 Operating income $ 40,318 $ 38,310 $ 32,246 Segment operating income as a percentage of segment revenues 24.0 % 25.6 % 24.1 % Business Advisory: Revenues $ 207,753 $ 151,543 $ 116,892 Operating income $ 46,600 $ 29,382 $ 31,233 Segment operating income as a percentage of segment revenues 22.4 % 19.4 % 26.7 % All Other: (1) Revenues $ — $ — $ 1,222 Operating loss $ — $ — $ (1,718 ) Segment operating loss as a percentage of segment revenues N/A N/A N/M Total Company: Revenues $ 732,570 $ 726,272 $ 699,010 Reimbursable expenses 75,175 71,712 70,013 Total revenues and reimbursable expenses $ 807,745 $ 797,984 $ 769,023 Segment operating income $ 205,679 $ 215,595 $ 231,321 Items not allocated at the segment level: Other operating expenses 120,718 111,852 112,164 Litigation and other losses (gains), net 1,111 (1,990 ) (9,476 ) Depreciation and amortization 38,213 31,499 25,135 Goodwill impairment charges (2) 253,093 — — Other expense, net 15,048 15,077 19,933 Income (loss) from continuing operations before taxes $ (222,504 ) $ 59,157 $ 83,565 (1) During 2015, we wound down the businesses within our All Other operating segment, which consisted of our public sector consulting practice and our foreign consulting operations based in the Middle East. We did not generate any revenues from our All Other segment during 2016 and 2017. (2) The goodwill impairment charges are not allocated at the segment level because the underlying goodwill asset is reflective of our corporate investment in the segments. We do not include the impact of goodwill impairment charges in our evaluation of segment performance. N/M – Not Meaningful N/A – Not Applicable
Segment Assets	As of December 31, Segment Assets: 2017 2016 2015 Healthcare $ 70,097 $ 69,274 $ 84,088 Education 31,367 33,094 28,192 Business Advisory 58,217 43,151 29,609 Unallocated assets (1) 877,247 1,007,696 1,017,654 Total assets $ 1,036,928 $ 1,153,215 $ 1,159,543 (1) Unallocated assets includes goodwill and intangible assets and our convertible debt investment, as management does not evaluate these items at the segment level when assessing segment performance or allocating resources. Refer to Note 5 “Goodwill and Intangible Assets" and Note 12 "Fair Value of Financial Instruments" for further information on these assets.

Valuation and Qualifying Acco44

Valuation and Qualifying Accounts (Tables)	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Summary of Allowances for Doubtful Accounts and Unbilled Services and Valuation Allowance for Deferred Tax Assets	The table below sets forth the changes in the carrying amount of our allowances for doubtful accounts and unbilled services and valuation allowance for deferred tax assets for the years ended December 31, 2017 , 2016 , and 2015 . Beginning balance Additions (1) Deductions Ending balance Year ended December 31, 2015: Allowances for doubtful accounts and unbilled services $ 14,129 40,003 37,246 $ 16,886 Valuation allowance for deferred tax assets $ 2,431 1,212 1,401 $ 2,242 Year ended December 31, 2016: Allowances for doubtful accounts and unbilled services $ 16,886 48,901 44,528 $ 21,259 Valuation allowance for deferred tax assets $ 2,242 113 1,729 $ 626 Year ended December 31, 2017: Allowances for doubtful accounts and unbilled services $ 21,259 43,888 40,648 $ 24,499 Valuation allowance for deferred tax assets $ 626 793 172 $ 1,247 (1) Additions to allowances for doubtful accounts and unbilled services are charged to revenues to the extent the provision relates to fee adjustments and other discretionary pricing adjustments. To the extent the provision relates to a client’s inability to make required payments on accounts receivables, the provision is charged to operating expenses. Additions also include allowances acquired in business acquisitions, which were not material in any period presented.

Selected Quarterly Financial 45

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information [Table Text Block]	Quarter Ended 2017 Mar. 31 Jun. 30 Sep. 30 Dec. 31 Revenues $ 188,849 $ 181,418 $ 176,376 $ 185,927 Reimbursable expenses 16,950 20,930 17,982 19,313 Total revenues and reimbursable expenses 205,799 202,348 194,358 205,240 Gross profit 70,203 64,981 59,847 71,540 Operating income (loss) 14,149 (200,575 ) 6,098 (27,128 ) Net income (loss) from continuing operations 5,155 (150,482 ) 4,132 (29,310 ) Income (loss) from discontinued operations, net of tax 143 309 238 (302 ) Net income (loss) 5,298 (150,173 ) 4,370 (29,612 ) Net earnings (loss) per basic share: Net income (loss) from continuing operations $ 0.24 $ (7.00 ) $ 0.19 $ (1.36 ) Income (loss) from discontinued operations, net of tax 0.01 0.01 0.01 (0.02 ) Net income (loss) $ 0.25 $ (6.99 ) $ 0.20 $ (1.38 ) Net earnings (loss) per diluted share: Net income (loss) from continuing operations $ 0.24 $ (7.00 ) $ 0.19 $ (1.36 ) Income (loss) from discontinued operations, net of tax 0.01 0.01 0.01 (0.02 ) Net income (loss) $ 0.25 $ (6.99 ) $ 0.20 $ (1.38 ) Weighted average shares used in calculating earnings per share: Basic 21,239 21,492 21,505 21,515 Diluted 21,474 21,492 21,622 21,515	Quarter Ended 2016 Mar. 31 Jun. 30 Sep. 30 Dec. 31 Revenues $ 180,489 $ 184,259 $ 183,400 $ 178,124 Reimbursable expenses 16,561 18,982 19,093 17,076 Total revenues and reimbursable expenses 197,050 203,241 202,493 195,200 Gross profit 65,180 77,138 71,131 60,090 Operating income 14,376 28,209 23,240 8,409 Net income from continuing operations 6,866 16,139 12,288 4,187 Income (loss) from discontinued operations, net of tax (864 ) (970 ) 4 (33 ) Net income 6,002 15,169 12,292 4,154 Net earnings per basic share: Net income from continuing operations $ 0.33 $ 0.77 $ 0.58 $ 0.20 Income (loss) from discontinued operations, net of tax (0.05 ) (0.05 ) — — Net income $ 0.28 $ 0.72 $ 0.58 $ 0.20 Net earnings per diluted share: Net income from continuing operations $ 0.32 $ 0.76 $ 0.57 $ 0.19 Income (loss) from discontinued operations, net of tax (0.04 ) (0.05 ) — — Net income $ 0.28 $ 0.71 $ 0.57 $ 0.19 Weighted average shares used in calculating earnings per share: Basic 21,114 21,061 21,076 21,083 Diluted 21,460 21,376 21,445 21,473

Summary of Significant Accoun46

Summary of Significant Accounting Policies (Details)	3 Months Ended			6 Months Ended	12 Months Ended
	Dec. 31, 2017USD ($)	Sep. 30, 2017	Jun. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Dec. 31, 2017USD ($)Reporting_UnitSegmentBilling	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2014USD ($)
Accounting Policies [Abstract]
Number of billing arrangements for revenue recognition | Billing					4
Cash and Cash Equivalents [Line Items]
Goodwill, Impairment Loss					$ 253,093,000	$ 0	$ 0
Unamortized capitalized software development costs	$ 2,000,000				2,000,000	1,400,000
Amortized capitalized software development costs					800,000	1,100,000	1,000,000
Impairment of long-lived assets					$ 0	0	0
Impairment of intangible assets and goodwill						0	0
Number of Reporting Units | Reporting_Unit					6
Number of Operating Segments | Segment					3
Deferred lease incentives	$ 15,333,000				$ 15,333,000	10,703,000
Sponsorship and advertising costs					6,600,000	$ 7,100,000	6,400,000
Aggregate principal amount								$ 250,000,000
Debt Instrument, Interest Rate, Stated Percentage								1.25%
Foreign currency translation gain (loss), net of tax					$ 400,000		$ 1,600,000
Maximum [Member]
Cash and Cash Equivalents [Line Items]
Cash and Cash Equivalent maturity period					3 months
Computers, related equipment and software [Member] | Maximum [Member]
Cash and Cash Equivalents [Line Items]
Depreciated over and estimated useful life					P4Y
Computers, related equipment and software [Member] | Minimum [Member]
Cash and Cash Equivalents [Line Items]
Depreciated over and estimated useful life					P2Y
Furniture and fixtures [Member]
Cash and Cash Equivalents [Line Items]
Depreciated over and estimated useful life					P5Y
Aircraft [Domain]
Cash and Cash Equivalents [Line Items]
Depreciated over and estimated useful life					P10Y
Deferred Tax Asset [Domain]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description			1,500,000
Health Care [Member]
Cash and Cash Equivalents [Line Items]
Goodwill, Impairment Loss			$ 209,600,000	$ 209,600,000	$ (208,081,000)
Incorrect netting of deferred tax assets and deferred tax liabilities [Member] | Deferred Tax Asset [Domain]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description		1.5
Goodwill, Impairment Loss [Member] | Health Care [Member] | Goodwill [Member]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description	1.5
Goodwill, Impairment Loss [Member] | Health Care [Member] | Deferred Tax Asset [Domain]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description	1.5
Goodwill, Impairment Loss [Member] | Health Care [Member] | Goodwill, Impairment Loss [Member]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description	1.5
Goodwill, Impairment Loss [Member] | Health Care [Member] | Income Tax Expense [Member]
Cash and Cash Equivalents [Line Items]
Error Corrections and Prior Period Adjustments, Description	1.5

Summary of Significant Accoun47

Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess Tax Benefit from Share-based Compensation, Financing Activities		$ 0.9	$ 3.6
Stock-based compensation forfeiture allowance				$ 0.4
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 0.5
Income Tax Expense [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ (1.8)

Discontinued Operations - Addit

Discontinued Operations - Additional Information (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on disposal									$ 931,000	$ 0	$ (2,303,000)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	$ (302,000)	$ 238,000	$ 309,000	$ 143,000	$ (33,000)	$ 4,000	$ (970,000)	$ (864,000)	388,000	(1,863,000)	(2,843,000)
Discontinued operations [Member] | Huron Legal [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets	0				0				0	0
Disposal Group, Including Discontinued Operation, Consideration											110,100,000
Loss on disposal											(2,303,000)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											$ (2,843,000)
Disposal Group, Including Discontinued Operation, Liabilities	$ 0				$ 0				$ 0	$ 0

Discontinued Operations - Incom

Discontinued Operations - Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating expenses and other operating gains:
Restructuring charges (1)									$ 6,246	$ 9,592	$ 3,329
Loss on disposal									931	0	(2,303)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	$ (302)	$ 238	$ 309	$ 143	$ (33)	$ 4	$ (970)	$ (864)	388	(1,863)	(2,843)
Employee Severance [Member]
Operating expenses and other operating gains:
Restructuring charges (1)									3,700	7,300	2,800
Huron Legal [Member]
Operating expenses and other operating gains:
Restructuring charges (1)											13,300
Huron Legal [Member] | Facility Closing [Member]
Operating expenses and other operating gains:
Restructuring charges (1)											1,100
Huron Legal [Member] | Facility Closing [Member] | Sale of Huron Legal [Member]
Operating expenses and other operating gains:
Restructuring charges (1)											6,100
Huron Legal [Member] | One-time Termination Benefits [Member] | Sale of Huron Legal [Member]
Operating expenses and other operating gains:
Restructuring charges (1)											5,100
Huron Legal [Member] | Employee Severance [Member]
Operating expenses and other operating gains:
Restructuring charges (1)											1,000
Discontinued operations [Member] | Huron Legal [Member]
Revenues and reimbursable expenses:
Revenues											142,578
Reimbursable expenses											3,148
Total revenues and reimbursable expenses											142,578
Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses):
Direct costs											98,633
Amortization of intangible assets and software development costs											15,974
Reimbursable expenses											3,148
Operating expenses and other operating gains:
Restructuring charges (1)									1,000	2,000
Total operating expenses and other operating gain											42,686
Operating income											1,259
Total operating expenses and other operating gains											(1,259)
Other expense, net											(13)
Income from discontinued operations before taxes									1,000	2,800	(1,057)
Loss on disposal											(2,303)
Total loss from discontinued operations before taxes									1,000	2,800	(1,057)
Income tax benefit (2)									$ 600	$ 900	1,786
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											(2,843)
Sales [Member] | Discontinued operations [Member] | Huron Legal [Member]
Revenues and reimbursable expenses:
Revenues											139,430
Total revenues and reimbursable expenses											139,430
Cost of Sales [Member] | Discontinued operations [Member] | Huron Legal [Member]
Revenues and reimbursable expenses:
Reimbursable expenses											3,153
Direct costs and reimbursable expenses (exclusive of depreciation and amortization shown in operating expenses):
Direct costs											95,247
Amortization of intangible assets and software development costs											233
Reimbursable expenses											3,153
Operating Expense [Member] | Discontinued operations [Member] | Huron Legal [Member]
Operating expenses and other operating gains:
Selling, general and administrative expenses											20,640
Restructuring charges (1)											13,341
Other gain											(900)
Depreciation and amortization											9,605
Operating Income (Loss) [Member] | Discontinued operations [Member] | Huron Legal [Member]
Operating expenses and other operating gains:
Income from discontinued operations before taxes											1,246
Total loss from discontinued operations before taxes											$ 1,246

Discontinued Operations - Cash

Discontinued Operations - Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Share-based compensation	$ 14,838	$ 16,577	$ 21,487
Purchases of property and equipment	$ 24,402	$ 13,936	18,571
Discontinued operations [Member] | Huron Legal [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Amortization of intangible assets and software development costs			15,974
Share-based compensation			2,215
Purchases of property and equipment			6,234
Significant non-cash investing items of discontinued operations:
Contingent consideration related to business acquisitions			$ 900

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Mar. 01, 2017	Feb. 12, 2015	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Business Combination, Provisional Information, Initial Accounting Incomplete, Reasons											The current fair values of assets acquired and liabilities assumed are considered preliminary and are based on the information that is currently available. We believe that the information provides a reasonable basis for estimating the preliminary fair values of assets acquired and liabilities assumed, but certain items, such as working capital amounts, may be subject to change as additional information is received. Thus, the provisional measurements of fair value and goodwill are subject to change. We will finalize the valuation in the first quarter of 2018.
Share Price			$ 40.45								$ 40.45
Contingent consideration related to business acquisitions			$ 15,489				$ 8,754				$ 15,489	$ 8,754	$ 2,963
Revenues			185,927	$ 176,376	$ 181,418	$ 188,849	178,124	$ 183,400	$ 184,259	$ 180,489	732,570	726,272	699,010
Operating income (loss)			$ (27,128)	$ 6,098	(200,575)	14,149	$ 8,409	$ 23,240	$ 28,209	$ 14,376	(207,456)	74,234	103,498
Amortization of Intangible Assets											35,000	33,100	28,700
Innosight Holdings, LLC [Member]
Business Acquisition [Line Items]
Effective date of acquisition	Mar. 1, 2017
Outstanding stock from the existing shareholders	100.00%
Acquisition date fair value of the consideration	$ 113,607
Borrowings under credit facility	$ 89,000
Common stock issued	221,558
Acquisition date fair value	$ 9,560
Share Price	$ 43.15
Contingent consideration related to business acquisitions	$ 12,050
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 35,000
Weighted-average amortization period	5 years 7 months
Goodwill expected to be deductible for income tax purpose	$ 87,400
Revenues											34,300
Operating income (loss)											(900)
Amortization of Intangible Assets											3,400
Expenses incurred					$ 300	$ 1,400					1,700
Pro Forma Adjustments, Additional Expense											$ 600	$ 11,400
Studer Group
Business Acquisition [Line Items]
Effective date of acquisition		Feb. 12, 2015
Outstanding stock from the existing shareholders		100.00%
Date of acquisition agreement		Jan. 26, 2015
Acquisition date fair value of the consideration		$ 325,186
Borrowings under credit facility		$ 102,000
Common stock issued		28,486
Acquisition date fair value		$ 2,204
Share Price		$ 77.35
Weighted-average amortization period		6 years 4 months
Goodwill expected to be deductible for income tax purpose		$ 119,500
Revenues													79,900
Operating income (loss)													5,100
Amortization of Intangible Assets													21,300
Expenses incurred		$ 2,100											1,200	$ 900
Pro Forma Adjustments, Additional Expense													$ 2,400

Acquisitions - Summary of Fair

Acquisitions - Summary of Fair Value of Consideration Transferred (Details) - USD ($) $ in Thousands	Mar. 01, 2017	Feb. 12, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Contingent consideration related to business acquisitions			$ 15,489	$ 8,754	$ 2,963
Innosight Holdings, LLC [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 90,725
Acquisition date fair value	9,560
Contingent consideration related to business acquisitions	12,050
Consideration transferred net working capital adjustment	1,272
Acquisition date fair value of the consideration	$ 113,607
Studer Group
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 323,237
Acquisition date fair value		2,204
Consideration transferred net working capital adjustment		255
Acquisition date fair value of the consideration		$ 325,186

Acquisitions - Preliminary Allo

Acquisitions - Preliminary Allocation of the Purchase Price to the Fair Value of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Mar. 01, 2017	Dec. 31, 2016	Dec. 31, 2015	Feb. 12, 2015
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Costs in Excess of Billings, Current	$ 57,618		$ 51,290
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract]
Goodwill	$ 645,750		$ 799,862	$ 751,400
Innosight Holdings, LLC [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Accounts receivable		$ 7,752
Costs in Excess of Billings, Current		1,881
Prepaid expenses and other current assets		468
Property and equipment		419
Intangible assets		18,015
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract]
Accounts payable		531
Accrued expenses and other current liabilities		894
Accrued payroll and related benefits		883
Deferred revenues		30
Total identifiable net assets		26,197
Goodwill		87,410
Total purchase price		$ 113,607
Studer Group
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Accounts receivable					$ 14,906
Prepaid expenses and other current assets					1,385
Deferred income tax asset					4,335
Property and equipment					4,509
Intangible assets					97,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities [Abstract]
Accounts payable					760
Accrued expenses and other current liabilities					2,868
Accrued payroll and related benefits					1,574
Deferred revenues					2,449
Deferred income tax liability					21,263
Other non-current liabilities					1,211
Total identifiable net assets					92,510
Goodwill					232,676
Total purchase price					$ 325,186

Acquisitions - Schedule of Comp

Acquisitions - Schedule of Components of Identifiable Intangible Assets Acquired and their Estimated Useful Lives (Details) - USD ($) $ in Thousands	Mar. 01, 2017	Feb. 12, 2015	Dec. 31, 2017
Off-Market Favorable Lease [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life in years			3 years
Publishing content [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Useful life in years			3 years
Innosight Holdings, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 18,015
Innosight Holdings, LLC [Member] | Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 9,500
Useful life in years	6 years
Innosight Holdings, LLC [Member] | Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 6,000
Useful life in years	6 years
Innosight Holdings, LLC [Member] | Customer contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 1,000
Useful life in years	1 year
Innosight Holdings, LLC [Member] | Non-competition Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 1,300
Useful life in years	5 years
Innosight Holdings, LLC [Member] | Off-Market Favorable Lease [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 215
Useful life in years	1 year
Studer Group
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 97,500
Studer Group | Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 42,400
Useful life in years		9 years
Studer Group | Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 22,800
Useful life in years		5 years
Studer Group | Customer contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 25,100
Useful life in years		4 years
Studer Group | Technology-Based Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 3,900
Useful life in years		3 years
Studer Group | Publishing content [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 3,300
Useful life in years		3 years

Acquisitions - Summary of Suppl

Acquisitions - Summary of Supplemental Pro Forma Consolidated Results of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Innosight Holdings, LLC [Member]
Business Combination, Separately Recognized Transactions [Line Items]
Business acquisition, pro forma revenue	$ 741,695	$ 769,114
Business acquisition, pro forma net income (loss)	$ (167,346)	$ 42,760
Business acquisition, pro forma earnings per share, basic (in USD per share)	$ (7.79)	$ 2.01
Business acquisition, pro forma earnings per share, diluted (in USD per share)	$ (7.79)	$ 1.98
Studer Group
Business Combination, Separately Recognized Transactions [Line Items]
Business acquisition, pro forma revenue			$ 709,813
Business acquisition, pro forma net income (loss)			$ 63,600
Business acquisition, pro forma earnings per share, basic (in USD per share)			$ 2.87
Business acquisition, pro forma earnings per share, diluted (in USD per share)			$ 2.81

Goodwill and Intangible Asset56

Goodwill and Intangible Assets - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill			$ 1,041,826	$ 942,845	$ 894,383
Accumulated impairment losses			(396,076)	(142,983)	(142,983)
Goodwill, net beginning balance		$ 799,862	799,862	751,400
Goodwill recorded in connection with business combinations			98,443	48,362
Goodwill, Impairment Loss			(253,093)	0	0
Goodwill, Transfers			0
Goodwill, Written off Related to Sale of Business Unit			(568)
Foreign currency translation			1,106	100
Goodwill, net ending balance			645,750	799,862	751,400
Health Care [Member]
Goodwill [Line Items]
Goodwill			636,810	636,802	610,264
Accumulated impairment losses			(208,081)	0	0
Goodwill, net beginning balance		636,802	636,802	610,264
Goodwill recorded in connection with business combinations			8	26,538
Goodwill, Impairment Loss	$ (209,600)	(209,600)	208,081
Foreign currency translation			0	0
Goodwill, net ending balance			428,729	636,802	610,264
Education [Member]
Goodwill [Line Items]
Goodwill			102,829	102,906	102,906
Accumulated impairment losses			0	0	0
Goodwill, net beginning balance		102,906	102,906	102,906
Goodwill recorded in connection with business combinations			10,252	0
Goodwill, Transfers			(10,794)
Foreign currency translation			465	0
Goodwill, net ending balance			102,829	102,906	102,906
Business Advisory [Member]
Goodwill [Line Items]
Goodwill			302,187	203,137	181,213
Accumulated impairment losses			(187,995)	(142,983)	(142,983)
Goodwill, net beginning balance		$ 60,154	60,154	38,230
Goodwill recorded in connection with business combinations			88,183	21,824
Goodwill, Transfers			10,794
Foreign currency translation			641	100
Goodwill, net ending balance			$ 114,192	$ 60,154	$ 38,230

Goodwill and Intangible Asset57

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended	12 Months Ended
	Dec. 31, 2017	Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Nov. 30, 2017
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit				$ 568
Loss on disposal				931	$ 0	$ (2,303)
Goodwill, Impairment Loss				(253,093)	$ 0	$ 0
Goodwill, Transfers				0
Health Care [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							40.00%
Education [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							119.60%
Business Advisory [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							115.00%
Enterprise Solutions and Analytics [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss				(45,012)
Strategy and Innovation [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							33.00%
Life Sciences [Member]
Goodwill [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							14.00%
Health Care [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss		$ (209,600)	$ (209,600)	$ 208,081
Goodwill, Impairment Loss [Member] | Goodwill, Impairment Loss [Member] | Health Care [Member]
Goodwill [Line Items]
Error Corrections and Prior Period Adjustments, Description	1.5

Goodwill and Intangible Asset58

Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Intangible assets
Gross carrying amount		$ 178,888	$ 155,751
Accumulated Amortization		106,577	74,403
Customer contracts [Member]
Intangible assets
Gross carrying amount		25,154	26,497
Accumulated Amortization		$ 24,751	21,295
Customer contracts [Member] | Minimum [Member]
Intangible assets
Useful life in years		1 year
Customer contracts [Member] | Maximum [Member]
Intangible assets
Useful life in years		4 years
Customer relationships [Member]
Intangible assets
Gross carrying amount		$ 106,195	89,279
Accumulated Amortization		$ 51,588	34,827
Customer relationships [Member] | Minimum [Member]
Intangible assets
Useful life in years		4 years
Customer relationships [Member] | Maximum [Member]
Intangible assets
Useful life in years		13 years
Non-competition Agreements [Member]
Intangible assets
Gross carrying amount		$ 5,163	3,685
Accumulated Amortization		$ 2,637	1,697
Non-competition Agreements [Member] | Minimum [Member]
Intangible assets
Useful life in years		3 years
Non-competition Agreements [Member] | Maximum [Member]
Intangible assets
Useful life in years		5 years
Trade names [Member]
Intangible assets
Gross carrying amount		$ 29,016	22,930
Accumulated Amortization		$ 18,915	11,652
Trade names [Member] | Minimum [Member]
Intangible assets
Useful life in years		2 years
Trade names [Member] | Maximum [Member]
Intangible assets
Useful life in years		6 years
Technology-Based Intangible Assets [Member]
Intangible assets
Gross carrying amount		$ 9,340	8,970
Accumulated Amortization		$ 5,098	2,667
Technology-Based Intangible Assets [Member] | Minimum [Member]
Intangible assets
Useful life in years		3 years
Technology-Based Intangible Assets [Member] | Maximum [Member]
Intangible assets
Useful life in years		5 years
Publishing content [Member]
Intangible assets
Useful life in years		3 years
Gross carrying amount		$ 3,300	3,300
Accumulated Amortization		$ 3,163	2,062
Off-Market Favorable Lease [Member]
Intangible assets
Useful life in years		3 years
Gross carrying amount		$ 720	720
Accumulated Amortization		425	203
In Process Research and Development [Member]
Intangible assets
Indefinite-Lived Intangible Assets (Excluding Goodwill)		$ 0	$ 370
MyRounding [Member] | Technology-Based Intangible Assets [Member]
Intangible assets
Useful life in years	5 years

Goodwill and Intangible Asset59

Goodwill and Intangible Assets - Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of Intangible Assets	$ 35,000	$ 33,100	$ 28,700
Finite-Lived Intangible Assets, Amortization Expense, Year Two	23,936
Finite-Lived Intangible Assets, Amortization Expense, Year Three	17,279
Finite-Lived Intangible Assets, Amortization Expense, Year Four	12,116
Finite-Lived Intangible Assets, Amortization Expense, Year Five	8,070
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 6,092

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Depreciation expense for property and equipment	$ 13.3	$ 12.5	$ 12.3

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property and equipment	$ 115,685	$ 99,948
Accumulated depreciation and amortization	(70,144)	(67,514)
Property and equipment, net	45,541	32,434
Computers, related equipment and software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	46,216	48,607
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	45,244	38,502
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	16,434	12,545
Assets under Construction [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	250	294
Aircraft [Domain]
Property, Plant and Equipment [Line Items]
Property and equipment	7,541	$ 0
Property and equipment, net	$ 6,500

Financing Arrangements - Summar

Financing Arrangements - Summary of Carrying Amounts of Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 343,008		$ 292,065
Long-term debt, net of current portion	342,507		292,065
Convertible Debt [Member]
Debt Instrument [Line Items]
Long-term debt	233,140		224,065
Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	105,000		$ 68,000
Promissory Note due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt	4,868	$ 5,100
Long-term Debt, Current Maturities	$ 501

Financing Arrangements Financin

Financing Arrangements Financing Arrangements - Summary of Debt Maturities (Details) $ in Thousands	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 501
Long-term Debt, Maturities, Repayments of Principal in Year Two	250,515
Long-term Debt, Maturities, Repayments of Principal in Year Three	105,529
Long-term Debt, Maturities, Repayments of Principal in Year Four	544
Long-term Debt, Maturities, Repayments of Principal in Year Five	559
Long-term Debt, Maturities, Repayments of Principal after Year Five	$ 2,221

Financing Arrangements - Additi

Financing Arrangements - Additional Information (Detail) $ / shares in Units, shares in Millions	Jun. 30, 2017USD ($)	Jun. 22, 2017	Mar. 31, 2015USD ($)	Sep. 30, 2014USD ($)$ / sharesshares	Apr. 04, 2013	Mar. 31, 2015USD ($)	Sep. 30, 2014USD ($)$ / sharesshares	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Aggregate principal amount				$ 250,000,000			$ 250,000,000
Conversion price of convertible notes (in USD per share) | $ / shares				$ 79.89			$ 79.89
Payments of Debt Issuance Costs								$ 408,000	$ 0	$ 0
Deferred income taxes, net								1,097,000	35,633,000
Long-term debt								343,008,000	292,065,000
Duration of LIBOR		1 month			1 month
Property and equipment, net								45,541,000	32,434,000
Debt Instrument, Interest Rate, Stated Percentage				1.25%			1.25%
Warrant [Member]
Debt Instrument [Line Items]
Common stock purchased (in shares) | shares				3.1			3.1
Common stock price (in USD per share) | $ / shares				$ 97.12			$ 97.12
Aggregate proceeds from the sale of warrants				$ 23,600,000
Note Hedge [Member]
Debt Instrument [Line Items]
Common stock purchased (in shares) | shares				3.1			3.1
Aggregate amount for convertible hedge				$ 42,100,000
Deferred tax asset				16,500,000			$ 16,500,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Aggregate principal amount			$ 250,000,000	$ 250,000,000		$ 250,000,000	250,000,000	250,000,000	250,000,000
Debt Instrument, Unamortized Discount								14,668,000	22,520,000
Debt Issuance Costs, Net								$ 2,192,000	3,415,000
Number of common shares converted upon debt conversion for each $1000 principal amount				12.5170
Principal amount of notes per conversion				$ 1,000			$ 1,000
Conversion price of convertible notes (in USD per share) | $ / shares				$ 79.89			$ 79.89
Optional right of debt instrument holders to convert debt instrument into cash, portion of principal amount				100.00%
Earliest conversion date				Jul. 1, 2019
Concentration risk percentage				98.00%
Effective interest rate of debt				4.751%			4.751%
Remaining life of notes								1 year 9 months
Payments of Debt Issuance Costs							$ 7,300,000
Liability issuance costs				$ 6,200,000			6,200,000
Equity issuance costs				1,100,000			1,100,000
Deferred income taxes, net				$ 15,400,000			$ 15,400,000
Long-term debt								$ 233,140,000	224,065,000
Debt Instrument, Interest Rate, Stated Percentage				1.25%			1.25%
Debt Conversion, Original Debt, Due Date of Debt				Oct. 1, 2019
Convertible Debt [Member] | Minimum [Member]
Debt Instrument [Line Items]
Conversion price of convertible notes (in USD per share) | $ / shares				$ 79.89			$ 79.89
Number of least trading days required within 30 consecutive trading days				20 days
Number of consecutive trading days				30 days
Percentage of applicable conversion price				130.00%
Convertible Debt [Member] | Maximum [Member]
Debt Instrument [Line Items]
Conversion price of convertible notes (in USD per share) | $ / shares				$ 97.12			$ 97.12
Senior Secured Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit current borrowing capacity			$ 500,000,000			500,000,000
Period of revolving credit facility			5 years
Maturity date			Mar. 31, 2020
Optional increase In revolver			$ 100,000,000
Aggregate principal amount - Senior secured credit facility			$ 600,000,000			$ 600,000,000
Required payment on revolver related to convertible debt maturity term			90 days
Percentage of pledged voting stock in domestic subsidiaries			100.00%
Percentage of pledged voting stock in foreign subsidiaries			65.00%
Minimum interest coverage ratio			3.50			3.50
Actual consolidated leverage ratio								3.02
Actual interest coverage ratio								12.43
Long-term debt								$ 105,000,000	$ 68,000,000
Percentage of weighted average interest rate of borrowings								3.70%	2.50%
Outstanding letters of credit								$ 1,900,000	$ 4,800,000
Unused borrowing capacity under Credit Agreement								393,100,000
Senior Secured Credit Facility [Member] | Scenario One, Leverage Ratio [Member]
Debt Instrument [Line Items]
Maximum consolidated leverage ratio						3.25
Senior Secured Credit Facility [Member] | Scenario Two, Leverage Ratio [Member]
Debt Instrument [Line Items]
Maximum consolidated leverage ratio						3.75
Senior Secured Credit Facility [Member] | Minimum [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			0.25%
Senior Secured Credit Facility [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.25%
Senior Secured Credit Facility [Member] | Maximum [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.00%
Senior Secured Credit Facility [Member] | Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			2.00%
Promissory Note due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.97%
Long-term debt	$ 5,100,000							4,868,000
Debt Instrument, Maturity Date	Mar. 1, 2024
Repayment of Principal at Maturity Date	$ 1,500,000
Duration of LIBOR	1 month
Aircraft [Domain]
Debt Instrument [Line Items]
Property and equipment, net								$ 6,500,000

Financing Arrangements - Schedu

Financing Arrangements - Schedule of Notes (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2015	Sep. 30, 2014
Convertible Senior Notes [Line Items]
Proceeds				$ 250,000,000
Long-term debt	$ 343,008,000	$ 292,065,000
Convertible Debt [Member]
Convertible Senior Notes [Line Items]
Proceeds	250,000,000	250,000,000	$ 250,000,000	$ 250,000,000
Less: debt discount, net of amortization	(14,668,000)	(22,520,000)
Debt Issuance Costs, Net	2,192,000	3,415,000
Long-term debt	233,140,000	224,065,000
Equity component	$ 39,287,000	$ 39,287,000

Financing Arrangements - Summ66

Financing Arrangements - Summary of Interest Expense Recognized (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Expense Recognized [Line Items]
Contractual interest coupon	$ 3,125	$ 3,125	$ 3,125
Amortization of debt discount	7,851	7,488	7,141
Amortization of debt issuance costs	1,224	1,201	1,180
Convertible Debt [Member]
Interest Expense Recognized [Line Items]
Total interest expense recognized	$ 12,200	$ 11,814	$ 11,446

Capital Structure - Additional

Capital Structure - Additional Information (Detail) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Equity [Abstract]
Preferred stock, shares authorized	50,000,000
Preferred stock, shares approved or issued	0	0
Common stock, shares authorized	500,000,000	500,000,000
Common stock, par value (in USD per share)	$ 0.01	$ 0.01

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share Reconciliation [Abstract]
Net income (loss) from continuing operations	$ (29,310)	$ 4,132	$ (150,482)	$ 5,155	$ 4,187	$ 12,288	$ 16,139	$ 6,866	$ (170,505)	$ 39,480	$ 61,895
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(302)	238	309	143	(33)	4	(970)	(864)	388	(1,863)	(2,843)
Net income (loss)	$ (29,612)	$ 4,370	$ (150,173)	$ 5,298	$ 4,154	$ 12,292	$ 15,169	$ 6,002	$ (170,117)	$ 37,617	$ 59,052
Weighted average common shares outstanding-basic	21,515	21,505	21,492	21,239	21,083	21,076	21,061	21,114	21,439	21,084	22,136
Weighted average common stock equivalents									0	340	464
Weighted average common shares outstanding- diluted	21,515	21,622	21,492	21,474	21,473	21,445	21,376	21,460	21,439	21,424	22,600
Net earnings per basic share:
Net income from continuing operations, per basic share (in USD per share)	$ (1.36)	$ 0.19	$ (7)	$ 0.24	$ 0.20	$ 0.58	$ 0.77	$ 0.33	$ (7.95)	$ 1.87	$ 2.80
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	(0.02)	0.01	0.01	0.01	0	0	(0.05)	(0.05)	0.02	(0.09)	(0.13)
Net income, per basic share (in USD per share)	(1.38)	0.20	(6.99)	0.25	0.20	0.58	0.72	0.28	(7.93)	1.78	2.67
Net earnings per diluted share:
Net income from continuing operations, per diluted share (in USD per share)	(1.36)	0.19	(7)	0.24	0.19	0.57	0.76	0.32	(7.95)	1.84	2.74
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	(0.02)	0.01	0.01	0.01	0	0	(0.05)	(0.04)	0.02	(0.08)	(0.13)
Net income, per diluted share (in USD per share)	$ (1.38)	$ 0.20	$ (6.99)	$ 0.25	$ 0.19	$ 0.57	$ 0.71	$ 0.28	$ (7.93)	$ 1.76	$ 2.61

Earnings Per Share - Summary of

Earnings Per Share - Summary of Anti-dilutive Securities Excluded from Computation of Weighted Average Common Stock Equivalents (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	7,088	6,260	6,279
Restricted Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	636	2	21
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	194	0	0
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	3,129	3,129	3,129
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	3,129	3,129	3,129

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Accelerated Share Repurchases [Line Items]
Stock Repurchased and Retired During Period, Value	$ 55,265,000	$ 34,591,000
Share Repurchase Program [Member]
Accelerated Share Repurchases [Line Items]
Share repurchase authorized amount			$ 125,000,000
Shares repurchased	982,192	583,880
Stock Repurchased and Retired During Period, Value	$ 55,300,000	$ 34,600,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 35,100,000

Restructuring Charges - Additio

Restructuring Charges - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Charges [Line Items]
Restructuring additions	$ 6,246	$ 9,592	$ 3,329
Restructuring charge liability	5,514	10,979	8,702
Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions	3,700	7,300	2,800
Office Space Reductions [Member]
Restructuring Charges [Line Items]
Restructuring additions	2,400	1,500	500
Restructuring charge liability	4,247	5,773	6,379
Other Restructuring [Member]
Restructuring Charges [Line Items]
Restructuring additions		800
Restructuring charge liability	0	24	0
Employee Costs [Member]
Restructuring Charges [Line Items]
Restructuring charge liability	1,267	5,182	2,323
Healthcare and Business Advisory [Member] | Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions		6,400
Health Care [Member]
Restructuring Charges [Line Items]
Restructuring additions	2,100	5,800	1,200
Health Care [Member] | Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions	2,100
Corporate, Non-Segment [Member]
Restructuring Charges [Line Items]
Restructuring additions	2,900	3,200	1,000
Corporate, Non-Segment [Member] | Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions	400	900
Business Advisory [Member]
Restructuring Charges [Line Items]
Restructuring additions	1,100	600
Business Advisory [Member] | Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions	1,100
Other Segments [Member]
Restructuring Charges [Line Items]
Restructuring additions			1,100
Huron Legal [Member]
Restructuring Charges [Line Items]
Restructuring additions			13,300
Huron Legal [Member] | Employee Severance [Member]
Restructuring Charges [Line Items]
Restructuring additions			$ 1,000
Huron Legal [Member] | Discontinued operations [Member]
Restructuring Charges [Line Items]
Restructuring additions	$ 1,000	$ 2,000

Restructuring Charges Restructu

Restructuring Charges Restructuring Charges - Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Restructuring Reserve [Roll Forward]
Restructuring reserve, period start	$ 10,979	$ 8,702
Restructuring additions	6,395	9,724
Payments for restructuring	10,466	8,812
Restructuring reserve adjustments	(1,168)	1,693
Noncashrestructuringadjustments	(226)	(328)
Restructuring reserve, period end	5,514	10,979
Employee Costs [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, period start	5,182	2,323
Restructuring additions	3,859	9,082
Payments for restructuring	7,611	5,906
Restructuring reserve adjustments	(117)	(317)
Noncashrestructuringadjustments	(46)	0
Restructuring reserve, period end	1,267	5,182
Office Space Reductions [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, period start	5,773	6,379
Restructuring additions	2,426	57
Payments for restructuring	2,860	2,424
Restructuring reserve adjustments	(973)	1,765
Noncashrestructuringadjustments	(119)	(4)
Restructuring reserve, period end	4,247	5,773
Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, period start	24	0
Restructuring additions	110	585
Payments for restructuring	5	482
Restructuring reserve adjustments	(78)	245
Noncashrestructuringadjustments	(61)	(324)
Restructuring reserve, period end	$ 0	$ 24

Derivative Instruments and He73

Derivative Instruments and Hedging Activity - Additional Information (Detail) - USD ($)	Jun. 22, 2017	Apr. 04, 2013	Dec. 31, 2017	Apr. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Interest rate swap agreement, effective date	Aug. 31, 2017	Mar. 31, 2014
Interest rate swap agreement, end date	Aug. 31, 2022	Aug. 31, 2017
Interest rate swap agreement for a notional amount	$ 50,000,000	$ 60,000,000		$ 86,000,000
Duration of LIBOR	1 month	1 month
Percentage of fixed rate	1.90%	0.985%
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred			$ 100,000
Loss reclassification from accumulated OCI to income, estimate of time to transfer			12 months

Derivative Instruments and He74

Derivative Instruments and Hedging Activity - Fair Value Interest Rate Swaps Designated as Cash Flow Hedging Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other Noncurrent Assets [Member]
Fair Value interest rate swaps designated as cash flow hedging instruments
Fair value (derivative asset and liability)	$ 581	$ 0
Accrued expenses [Member]
Fair Value interest rate swaps designated as cash flow hedging instruments
Fair value (derivative asset and liability)	$ 48	$ 54

Fair Value of Financial Instr75

Fair Value of Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	$ 59,301	$ 53,408
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	8,881
Deferred Compensation Plan Assets [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	17,786	16,408
Contingent Consideration Liability [Member]
Assets, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	8,827	$ 2,063
Interest Rate Swap [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	533
Financial and Nonfinancial Liabilities, Fair Value Disclosure		54
Convertible Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	39,904	34,675	34,831
Promissory Note [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	1,078	2,325	$ 2,309
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	18,319	16,408
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	54
Fair Value, Inputs, Level 2 [Member] | Deferred Compensation Plan Assets [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	17,786	16,408
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	533
Financial and Nonfinancial Liabilities, Fair Value Disclosure		54
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	40,982	37,000
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	8,827
Fair Value, Inputs, Level 3 [Member] | Contingent Consideration Liability [Member]
Assets, Fair Value Disclosure [Abstract]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	8,827
Fair Value, Inputs, Level 3 [Member] | Convertible Debt Securities [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	39,904	34,675
Fair Value, Inputs, Level 3 [Member] | Promissory Note [Member]
Assets, Fair Value Disclosure [Abstract]
Assets, Fair Value Disclosure	$ 1,078	$ 2,325

Fair Value of Financial Instr76

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	Jun. 30, 2017	Dec. 30, 2011	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Sep. 30, 2014	Jul. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt			$ 343,008,000	$ 343,008,000	$ 292,065,000
Proceeds from note receivable				1,177,000	0	$ 0
Long-term Investments			$ 39,904,000	$ 39,904,000	34,675,000
Aggregate principal amount								$ 250,000,000
Share Price			$ 40.45	$ 40.45
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure			$ 59,301,000	$ 59,301,000	53,408,000
Convertible Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt			233,140,000	233,140,000	224,065,000
Aggregate principal amount			250,000,000	250,000,000	250,000,000		$ 250,000,000	$ 250,000,000
Debt Instrument, Convertible, Carrying Amount of Equity Component			39,287,000	39,287,000	39,287,000
Senior Secured Credit Facility [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt			105,000,000	105,000,000	68,000,000
Promissory Note due 2024 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 5,100,000		4,868,000	4,868,000
Debt Instrument, Maturity Date	Mar. 1, 2024
Convertible Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure			39,904,000	$ 39,904,000	34,675,000	34,831,000
Convertible Debt Securities [Member] | Shorelight Holdings Llc [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Investments									$ 27,900,000
Debt Instrument, Maturity Date				Jul. 1, 2020
Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)				$ 115,000	207,000
Promissory Note [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure			1,078,000	1,078,000	$ 2,325,000	$ 2,309,000
Promissory Note [Member] | Accounting Advisory Practice [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Non Cash Consideration For Sale Of Discontinued Operation		$ 3,500,000
Note Receivable, Term		4 years
Reduction in Principal of Amended Promissory Note				500,000
Proceeds from note receivable				$ 1,000,000
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			300,000
Held-to-maturity Securities, Debt Maturities, Date				Sep. 30, 2020
Fair Value Inputs, Discount Rate				10.00%
Promissory Note, Principal, Outstanding			1,000,000	$ 1,000,000
Prepaid Expenses and Other Current Assets [Member] | Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure			500,000	500,000
Other Noncurrent Assets [Member] | Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure			$ 600,000	$ 600,000

Fair Value of Financial Instr77

Fair Value of Financial Instruments - Summary of Carrying Amount and Estimated Fair Value of Convertible Notes (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	$ 343,008	$ 292,065
Convertible Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	233,140	224,065
Estimated fair value	$ 232,578	$ 245,018

Fair Value of Financial Instr78

Fair Value of Financial Instruments Fair Value of Financial Instruments - Promissory Note Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 59,301	$ 53,408
Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	115	207
Promissory Note [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	1,078	2,325	$ 2,309
Interest Income [Member] | Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(185)	$ (191)
Notes Receivable [Member] | Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	$ (1,177)

Fair Value of Financial Instr79

Fair Value of Financial Instruments Fair Value of Financial Instruments - Convertible Debt Investment Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 59,301	$ 53,408
Convertible Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	5,229
Convertible Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 39,904	34,675	$ 34,831
Shorelight Holdings Llc [Member] | Convertible Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)		$ (156)

Fair Value of Financial Instr80

Fair Value of Financial Instruments Fair Value of Financial Instruments - Contingent Consideration Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 22,828	$ 8,881
Contingent Consideration Liability [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	15,489	8,754
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(2,938)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease)	1,111	(1,990)
Contingent Consideration Liability [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	$ 8,827	$ 2,063
Foreign Currency Gain (Loss) [Member] | Contingent Consideration Liability [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease)	$ 339

Other Comprehensive Income (L81

Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Loss, Net of Tax (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments, beginning balance	$ (453)	$ (517)	$ (2,334)
Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax			(403)
Foreign currency translation adjustments, ending balance	1,149	(453)	(517)
Foreign currency translation adjustment, net of tax	1,602	64	1,817
Reclassification adjustment, net of tax			2,220
Unrealized loss on investment, beginning balance	4,088	4,185	(250)
Unrealized loss on investments	4,724	(97)	4,435
Other Comprehensive Income (Loss), Available for Sale Investment, Unrealized gain (loss)	4,231
Unrealized loss on investment, ending balance	8,812	4,088	4,185
Unrealized gain (loss) on cash flow hedges, beginning balance	(20)	(83)	(71)
Change in fair value	366	(179)	(492)
Reclassification adjustment into earnings	69	242	480
Unrealized gain (loss) on cash flow hedges, ending balance	409	(20)	(83)
Accumulated other comprehensive loss, beginning balance	3,615	3,585	(2,655)
Change in fair value	366	(179)	(492)
Reclassification adjustment into earnings	69	242	480
Accumulated other comprehensive loss, ending balance	10,370	$ 3,615	3,585
Huron Legal [Member] | Discontinued operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)			$ (2,200)
Retained Earnings [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	500
Convertible Debt Securities [Member] | Retained Earnings [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	493
Interest Rate Swap [Member] | Retained Earnings [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 0

Other Comprehensive Income (L82

Other Comprehensive Income (Loss) Other Comprehensive Income (Loss) - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Tax	$ 0	$ 0	$ 0
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	998	(59)	2,709
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	106	(122)	(327)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	$ 46	$ 161	$ 320

Employee Benefit and Deferred83

Employee Benefit and Deferred Compensation Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Postemployment Benefits [Abstract]
Employer contributions up to percent of employee's salaries	6.00%
Employer matching contributions	$ 20	$ 19.4	$ 17.6
Deferred compensation liability	$ 17.7	$ 16.4

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Detail) $ / shares in Units, $ in Millions	May 01, 2015shares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares	May 05, 2017shares	May 02, 2014shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retirement eligible provision, description		Eligible employees who have reached 62 years of age and have completed seven years of employment with the Company will continue vesting in their share-based awards after retirement, subject to certain conditions.
Retirement eligible provision, minimum age		62 years
Retirement eligible provision, minimum years of service		7 years
Share-based compensation expense | $		$ 14.8	$ 16.6	$ 19.2
Income tax benefits | $		5.8	$ 6.4	$ 7.6
Unrecognized compensation cost | $		$ 17.6
Unrecognized compensation cost, Period		2 years 2 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		194,000	194,000
Stock option awards granted		0	0	0
Exercise of stock options, shares		0
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Aggregate fair value of stock vested | $		$ 11.1	$ 14.9	$ 23.9
Weighted average grant date fair value (in USD per share) | $ / shares		$ 42.11	$ 56.28	$ 66.21
Performance-based stock activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate fair value of stock vested | $		$ 3.6	$ 3	$ 6.5
Weighted average grant date fair value (in USD per share) | $ / shares		$ 42.75	$ 55.52	$ 66.63
Performance-based stock activity [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		1 year
Performance-based stock activity [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $			$ 0.1
Exercise of stock options, shares		0		0
Executive Officer [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Stock options contractual term		10 years
Two Thousand And Twelve Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares authorized for issuance					804,000	850,000
Shares available for issuance		1,273,361
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		37,000
Stock Ownership Participation Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance	300,000	141,153
Restricted stock granted as a percentage of purchased shares	0.25
Two Thousand and Four Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number		157,000

Equity Incentive Plans - Schedu

Equity Incentive Plans - Schedule of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of Options (in thousands)
Outstanding, shares, beginning balance	194,000
Stock option awards granted	0	0	0
Exercise of stock options, shares	0
Forfeited or expired, shares	0
Outstanding, shares, ending balance	194,000	194,000
Exercisable, shares, ending balance	194,000
Weighted Average Exercise Price (in dollars)
Beginning balance, weighted average exercise price (in USD per share)	$ 29.06
Ending balance, weighted average exercise price (in USD per share)	29.06	$ 29.06
Exercisable, weighted average exercise price (in USD per share)	$ 29.06
Weighted-average remaining contractual term (years), option outstanding	3 years 3 months	4 years 3 months
Weighted-average remaining contractual term (years), options exercisable	3 years 3 months
Aggregate intrinsic value, option outstanding, beginning balance	$ 4.2
Aggregate intrinsic value, option outstanding, ending balance	2.2	$ 4.2
Aggregate intrinsic value, options exercisable, ending balance	$ 2.2

Equity Incentive Plans - Sche86

Equity Incentive Plans - Schedule of Restricted Stock Activity (Detail) - Restricted Stock Awards [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total
Nonvested stock, number of shares, beginning balance	622
Granted, number of shares	284
Vested, number of shares	(256)
Forfeited, number of shares	(76)
Nonvested stock, number of shares, ending balance	574	622
Weighted Average Grant Date Fair Value (in dollars)
Nonvested stock, weighted average grant date fair value, beginning balance (in USD per share)	$ 59.77
Weighted average grant date fair value (in USD per share)	42.11	$ 56.28	$ 66.21
Vested, weighted average grant date fair value (in USD per share)	57.80
Forfeited, weighted average grant date fair value (in USD per share)	59.18
Nonvested stock, weighted average grant date fair value, ending balance (in USD per share)	$ 51.97	$ 59.77
Two Thousand And Twelve Plan [Member]
Total
Nonvested stock, number of shares, beginning balance	610
Granted, number of shares	270
Vested, number of shares	(247)
Forfeited, number of shares	(72)
Nonvested stock, number of shares, ending balance	561	610
Stock Ownership Participation Program [Member]
Total
Nonvested stock, number of shares, beginning balance	12
Granted, number of shares	14
Vested, number of shares	(9)
Forfeited, number of shares	(4)
Nonvested stock, number of shares, ending balance	13	12

Equity Incentive Plans - Sche87

Equity Incentive Plans - Schedule of Performance-Based Stock Activity (Detail) - Performance-based stock activity [Member] - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Nonvested stock, number of shares, beginning balance	353,000	239,000
Granted, number of shares		328,000
Vested, number of shares		(85,000)
Forfeited, number of shares		(129,000)
Nonvested stock, number of shares, ending balance		353,000	239,000
Weighted Average Grant Date Fair Value (in dollars)
Nonvested stock, weighted average grant date fair value, beginning balance (in USD per share)	$ 44.45	$ 58.47
Weighted average grant date fair value (in USD per share)		42.75	$ 55.52	$ 66.63
Vested, weighted average grant date fair value (in USD per share)		61.66
Forfeited, weighted average grant date fair value (in USD per share)		54.85
Nonvested stock, weighted average grant date fair value, ending balance (in USD per share)		$ 44.45	$ 58.47
Scenario, Forecast [Member]
Number of Shares
Forfeited, number of shares	(235,000)

Equity Incentive Plans - Sche88

Equity Incentive Plans - Schedule of Stock Activity (Additional Information) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested performance-based shares outstanding		574,000	622,000
Forfeited, number of shares		(76,000)
Aggregate fair value of stock vested		$ 11.1	$ 14.9	$ 23.9
Performance-based stock activity [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested performance-based shares outstanding		353,000	239,000
Nonvested And Unearned Performance Shares		316,000
Forfeited, number of shares		(129,000)
Aggregate fair value of stock vested		$ 3.6	$ 3	$ 6.5
Performance-based stock activity [Member] | Scenario, Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited, number of shares	(235,000)

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense for Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal	$ (635)	$ 15,726	$ 4,806
State	545	1,623	2,380
Foreign	2,040	1,021	350
Total current	1,950	18,370	7,536
Deferred:
Federal	(46,103)	1,662	12,450
State	(6,576)	(274)	1,482
Foreign	(1,270)	(81)	202
Total deferred	(53,949)	1,307	14,134
Income tax expense for continuing operations	$ (51,999)	$ 19,677	$ 21,670

Income Taxes - Components of In

Income Taxes - Components of Income from Continuing Operations Before Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S.	$ (221,137)	$ 56,141	$ 85,164
Foreign	(1,367)	3,016	(1,599)
Income (loss) from continuing operations before taxes	$ (222,504)	$ 59,157	$ 83,565

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Income Tax Rate to Our Effective Tax Rate for Continuing Operations (Detail) - USD ($) number in Thousands, $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Net Income Tax Benefit Recognized from Intercompany Receivable Write Off	$ 2.7			$ 12.3
At U.S. statutory tax rate		0.00%	0.00%	0.00%
State income taxes, net of federal benefit		0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent		0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent		0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent		0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent		0.00%	0.00%	0.00%
Meals and entertainment		0.00%	0.00%	0.00%
Valuation allowance		0.00%	0.00%	0.00%
Foreign source income		0.00%	0.00%	0.00%
Tax credits / Section 199 Deduction		0.00%	0.00%	0.00%
Net tax (benefit) expense related to “check-the-box” election (1)		0.00%	0.00%	0.00%
Other		0.00%	0.00%	0.00%
Effective income tax expense rate for continuing operations		0.00%	0.00%	0.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)		$ 8,800
Realizable income tax benefit from check-the-box election				$ 13,000
Unrecognized tax benefit from check-the-box election				700
Net Income Tax Benefit Recognized from Intercompany Receivable Write Off	$ 2,700			$ 12,300
Effective tax rates for discontinued operations		60.00%	(33.40%)	169.00%
Valuation allowance		$ 1,247	$ 626
Federal and state tax credit carry forwards		1,900
Unrecognized Income Tax Benefits		813	3,340	$ 3,223	$ 2,488
Income Tax Examination, Penalties and Interest Accrued		$ 100	300
Foreign[Member]
Income Tax Disclosure [Line Items]
Income tax year is subject future examinations by federal tax authorities and local tax authorities		2010 through 2016
State and Local Jurisdiction [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forward expiration year		2,019
Income tax year is subject future examinations by federal tax authorities and local tax authorities		2010 through 2016
Federal [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forward expiration year		2,022
Income tax year is subject future examinations by federal tax authorities and local tax authorities		2013 through 2016
Huron Legal [Member] | Discontinued operations [Member]
Income Tax Disclosure [Line Items]
Tax benefit (expense)		$ 600	900	1,786
Income from discontinued operations before taxes		1,000	$ 2,800	$ (1,057)
Remeasurement of deferred tax balances [Member]
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)		7,900
Transition tax on accumulated foreign earnings [Member]
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)		600
Elimination of foreign credits on repatriation of foreign earnings as dividends [Member]
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)		$ 300

Income Taxes - Net Deferred Tax

Income Taxes - Net Deferred Tax Liabilities for Continuing Operations (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Share-based compensation	$ 5,674	$ 10,151
Accrued payroll and other liabilities	7,010	10,004
Deferred Tax Assets, Goodwill and Intangible Assets	2,137	0
Deferred lease incentives	4,352	4,666
Revenue recognition	1,586	1,983
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Restructuring Charges	1,104	2,230
Net operating loss carry-forwards	495	92
Tax credits	1,918	1,804
Deferred Tax Assets, Other	882	1,934
Total deferred tax assets	25,408	45,061
Valuation allowance	(1,247)	(626)
Net deferred tax assets	24,161	44,435
Convertible note hedge transactions	250	12,197
Deferred tax liabilities:
Prepaid expenses	(1,229)	(2,500)
Property and equipment	(4,031)	(2,933)
Intangibles and goodwill	0	(60,411)
Convertible note discount	(3)	(11,586)
Deferred Tax Liabilities, Investments	(3,110)	(2,600)
Other	(133)	(38)
Total deferred tax liabilities	(8,506)	(80,068)
Deferred Tax Assets, Net	$ 15,655
Net deferred tax liability for continuing operations		$ (35,633)

Income Taxes - Reconciliation94

Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 3,340	$ 3,223	$ 2,488
Decrease based on tax positions related to the prior year	(117)
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	(2,410)
Additions based on tax positions related to the current year		117	735
Unrecognized tax benefits, ending balance	$ 813	$ 3,340	$ 3,223

Commitments, Contingencies an95

Commitments, Contingencies and Guarantees - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments And Contingencies [Line Items]
Lease Expiration Date	Sep. 30, 2024
Rental expense, including operating costs and taxes	$ 14,300	$ 11,500	$ 12,300
Renewal Option, Expiration Date	Sep. 30, 2029
Fair Value, Measurements, Recurring [Member]
Commitments And Contingencies [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 22,828	8,881
Fair Value, Measurements, Recurring [Member] | Contingent Consideration Liability [Member]
Commitments And Contingencies [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	22,828	8,827	$ 2,063
Senior Secured Credit Facility [Member]
Commitments And Contingencies [Line Items]
Guarantees in the form of letters of credit	$ 1,900	4,800
Chicago, Illinois [Member]
Commitments And Contingencies [Line Items]
Period of renewal option that allow continue to occupy the majority of office space	5 years
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Commitments And Contingencies [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 22,828	8,827
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Contingent Consideration Liability [Member]
Commitments And Contingencies [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 22,828	$ 8,827

Commitments, Contingencies an96

Commitments, Contingencies and Guarantees - Future Minimum Rental Commitments Under Non-Cancelable Leases and Sublease Income (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 14,739
Operating Leases, Future Minimum Payments, Due in Two Years	13,444
Operating Leases, Future Minimum Payments, Due in Three Years	12,266
Operating Leases, Future Minimum Payments, Due in Four Years	11,298
Operating Leases, Future Minimum Payments, Due in Five Years	10,409
Operating Leases, Future Minimum Payments, Due Thereafter	37,804
Operating lease obligations, total	99,960
Operating Leases, Future Minimum Payments Receivable, Current	1,316
Operating Leases, Future Minimum Payments Receivable, in Two Years	291
Operating Leases, Future Minimum Payments Receivable, in Three Years	0
Operating Leases, Future Minimum Payments Receivable, in Four Years	0
Operating Leases, Future Minimum Payments Receivable, in Five Years	0
Operating Leases, Future Minimum Payments Receivable, Thereafter	0
Sublease income, total	$ 1,607

Segment Information - Additiona

Segment Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017Segment
Segment Reporting [Abstract]
Number of Operating Segments	3

Segment Information - Component

Segment Information - Components of Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of Segment Information
Revenues	$ 185,927	$ 176,376	$ 181,418	$ 188,849	$ 178,124	$ 183,400	$ 184,259	$ 180,489		$ 732,570	$ 726,272	$ 699,010
Operating income (loss)	(27,128)	6,098	(200,575)	14,149	8,409	23,240	28,209	14,376		(207,456)	74,234	103,498
Reimbursable expenses	19,313	17,982	20,930	16,950	17,076	19,093	18,982	16,561		75,175	71,712	70,013
Total revenues and reimbursable expenses	$ 205,240	$ 194,358	202,348	$ 205,799	$ 195,200	$ 202,493	$ 203,241	$ 197,050		807,745	797,984	769,023
Gain (Loss) Related To Litigation Settlement And Other Operating Gains										(1,111)	1,990	9,476
Depreciation and amortization expense										38,213	31,499	25,135
Goodwill, Impairment Loss										253,093	0	0
Other expense, net										15,048	15,077	19,933
Income (loss) from continuing operations before taxes										(222,504)	59,157	83,565
Health Care [Member]
Components of Segment Information
Goodwill, Impairment Loss			$ 209,600						$ 209,600	(208,081)
Operating Segments [Member]
Components of Segment Information
Operating income (loss)										205,679	215,595	231,321
Operating Segments [Member] | Health Care [Member]
Components of Segment Information
Revenues										356,909	424,912	446,887
Operating income (loss)										$ 118,761	$ 147,903	$ 169,560
Segment operating income as a percentage of segment revenues										33.30%	34.80%	37.90%
Operating Segments [Member] | Education [Member]
Components of Segment Information
Revenues										$ 167,908	$ 149,817	$ 134,009
Operating income (loss)										$ 40,318	$ 38,310	$ 32,246
Segment operating income as a percentage of segment revenues										24.00%	25.60%	24.10%
Operating Segments [Member] | Business Advisory [Member]
Components of Segment Information
Revenues										$ 207,753	$ 151,543	$ 116,892
Operating income (loss)										$ 46,600	$ 29,382	$ 31,233
Segment operating income as a percentage of segment revenues										22.40%	19.40%	26.70%
Operating Segments [Member] | All Other [Member]
Components of Segment Information
Revenues										$ 0	$ 0	$ 1,222
Operating income (loss)										0	0	(1,718)
Segment Reconciling Items [Member]
Components of Segment Information
Other operating expenses and gains										120,718	111,852	112,164
Gain (Loss) Related To Litigation Settlement And Other Operating Gains										1,111	(1,990)	(9,476)
Depreciation and amortization expense										38,213	31,499	25,135
Goodwill, Impairment Loss										253,093	0	0
Other expense, net										$ (15,048)	$ (15,077)	$ (19,933)

Segment Information - Segment A

Segment Information - Segment Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Assets:
Total assets	$ 1,036,928	$ 1,153,215	$ 1,159,543
Segment Reconciling Items [Member]
Segment Assets:
Total assets	877,247	1,007,696	1,017,654
Health Care [Member] | Operating Segments [Member]
Segment Assets:
Total assets	70,097	69,274	84,088
Education [Member] | Operating Segments [Member]
Segment Assets:
Total assets	31,367	33,094	28,192
Business Advisory [Member] | Operating Segments [Member]
Segment Assets:
Total assets	$ 58,217	$ 43,151	$ 29,609

Valuation and Qualifying Acc100

Valuation and Qualifying Accounts - Summary of Allowances for Doubtful Accounts and Unbilled Services and Valuation Allowance for Deferred Tax Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowances for doubtful accounts and unbilled services [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 21,259	$ 16,886	$ 14,129
Additions	43,888	48,901	40,003
Deductions	40,648	44,528	37,246
Ending balance	24,499	21,259	16,886
Valuation allowance for deferred tax assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	626	2,242	2,431
Additions	793	113	1,212
Deductions	172	1,729	1,401
Ending balance	$ 1,247	$ 626	$ 2,242

Selected Quarterly Financial101

Selected Quarterly Financial Data (unaudited) - Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 185,927	$ 176,376	$ 181,418	$ 188,849	$ 178,124	$ 183,400	$ 184,259	$ 180,489	$ 732,570	$ 726,272	$ 699,010
Reimbursable expenses	19,313	17,982	20,930	16,950	17,076	19,093	18,982	16,561	75,175	71,712	70,013
Total revenues and reimbursable expenses	205,240	194,358	202,348	205,799	195,200	202,493	203,241	197,050	807,745	797,984	769,023
Gross profit	71,540	59,847	64,981	70,203	60,090	71,131	77,138	65,180
Operating income (loss)	(27,128)	6,098	(200,575)	14,149	8,409	23,240	28,209	14,376	(207,456)	74,234	103,498
Net income (loss) from continuing operations	(29,310)	4,132	(150,482)	5,155	4,187	12,288	16,139	6,866	(170,505)	39,480	61,895
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(302)	238	309	143	(33)	4	(970)	(864)	388	(1,863)	(2,843)
Net income (loss)	$ (29,612)	$ 4,370	$ (150,173)	$ 5,298	$ 4,154	$ 12,292	$ 15,169	$ 6,002	$ (170,117)	$ 37,617	$ 59,052
Net earnings per basic share:
Net income from continuing operations, per basic share (in USD per share)	$ (1.36)	$ 0.19	$ (7)	$ 0.24	$ 0.20	$ 0.58	$ 0.77	$ 0.33	$ (7.95)	$ 1.87	$ 2.80
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share	(0.02)	0.01	0.01	0.01	0	0	(0.05)	(0.05)	0.02	(0.09)	(0.13)
Net income, per basic share (in USD per share)	(1.38)	0.20	(6.99)	0.25	0.20	0.58	0.72	0.28	(7.93)	1.78	2.67
Net earnings per diluted share:
Net income from continuing operations, per diluted share (in USD per share)	(1.36)	0.19	(7)	0.24	0.19	0.57	0.76	0.32	(7.95)	1.84	2.74
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share	(0.02)	0.01	0.01	0.01	0	0	(0.05)	(0.04)	0.02	(0.08)	(0.13)
Net income, per diluted share (in USD per share)	$ (1.38)	$ 0.20	$ (6.99)	$ 0.25	$ 0.19	$ 0.57	$ 0.71	$ 0.28	$ (7.93)	$ 1.76	$ 2.61
Weighted average shares used in calculating earnings per share:
Basic (shares)	21,515	21,505	21,492	21,239	21,083	21,076	21,061	21,114	21,439	21,084	22,136
Diluted (shares)	21,515	21,622	21,492	21,474	21,473	21,445	21,376	21,460	21,439	21,424	22,600