Heidrick & Struggles International (HSII) 10-Q 25 Oct 21 2021 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2021	Oct. 22, 2021
Cover [Abstract]
Document Type	10-Q
Document Period End Date	Sep. 30, 2021
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	0-25837
Entity Registrant Name	HEIDRICK & STRUGGLES INTERNATIONAL, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-2681268
City Area Code	(312)
Local Phone Number	496-1200
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	HSII
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		19,591,527
Entity Central Index Key	0001066605
Document Fiscal Year Focus	2021
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Address, Address Line One	233 South Wacker Drive
Entity Address, Address Line Two	Suite 4900
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60606-6303
Document Fiscal Period Focus	Q3
Amendment Flag	false
Document Information [Line Items]
Entity Shell Company	false
Entity Emerging Growth Company	false

Statement of Financial Position

Statement of Financial Position, Classified (Statement) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Assets, Current [Abstract]
Cash and Cash Equivalents, at Carrying Value	$ 348,292,000	$ 316,473,000
Marketable Securities, Current	0	19,999,000
Accounts Receivable, after Allowance for Credit Loss, Current	181,167,000	88,123,000
Prepaid Expense	26,624,000	18,956,000
Other Assets, Current	34,447,000	23,279,000
Income Taxes Receivable	4,386,000	5,856,000
Assets, Current	594,916,000	472,686,000
Assets, Noncurrent [Abstract]
Property, Plant and Equipment, Net	20,939,000	23,492,000
Operating Lease, Right-of-Use Asset	74,744,000	92,671,000
Assets for Plan Benefits, Defined Benefit Plan	13,672,000	14,425,000
Long-term Investments	34,738,000	31,369,000
Other Assets, Noncurrent	25,852,000	24,439,000
Goodwill	137,047,000	91,643,000
Other Intangible Assets, Net	10,223,000	1,129,000
Deferred Income Tax Assets, Net	36,501,000	35,958,000
Assets, Noncurrent	353,716,000	315,126,000
Assets	948,632,000	787,812,000
Liabilities, Current [Abstract]
Accounts Payable, Current	18,119,000	8,799,000
Employee-related Liabilities, Current	305,186,000	217,908,000
Deferred Revenue, Current	45,284,000	38,050,000
Operating Lease, Liability, Current	18,992,000	28,984,000
Other Liabilities, Current	22,723,000	23,311,000
Accrued Income Taxes, Current	14,742,000	1,186,000
Liabilities, Current	425,046,000	318,238,000
Liabilities, Noncurrent [Abstract]
Accrued Salaries and Benefits	52,623,000	56,925,000
Liability, Defined Benefit Plan, Noncurrent	55,804,000	53,496,000
Operating Lease, Liability, Noncurrent	63,336,000	86,816,000
Other Liabilities, Noncurrent	28,567,000	4,735,000
Liabilities, Noncurrent	200,330,000	201,972,000
Liabilities	625,376,000	520,210,000
Stockholders' Equity Attributable to Parent [Abstract]
Preferred Stock, Value, Issued	0	0
Common Stock, Value, Issued	196,000	196,000
Treasury Stock, Value	(181,000)	(8,041,000)
Additional Paid in Capital, Common Stock	229,115,000	231,048,000
Retained Earnings (Accumulated Deficit)	92,058,000	40,982,000
Accumulated Other Comprehensive Income (Loss), Net of Tax	2,068,000	3,417,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	323,256,000	267,602,000
Liabilities and Equity	$ 948,632,000	$ 787,812,000

Statement of Income (Statement)

Statement of Income (Statement) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue from Contract with Customer, Excluding Assessed Tax	$ 263,825,000	$ 143,544,000	$ 717,462,000	$ 460,628,000
Revenues	265,315,000	144,501,000	721,281,000	467,183,000
Labor and Related Expense	185,904,000	103,893,000	513,321,000	329,640,000
General and Administrative Expense	29,155,000	28,899,000	83,876,000	91,122,000
Asset Impairment Charges	0	0	0	32,970,000
Operating Expenses	231,973,000	182,734,000	639,625,000	511,250,000
Operating Income (Loss)	33,342,000	(38,233,000)	81,656,000	(44,067,000)
Interest Income (Expense), Net	90,000	(180,000)	207,000	160,000
Other Nonoperating Income (Expense)	145,000	1,819,000	6,260,000	460,000
Nonoperating Income (Expense)	235,000	1,639,000	6,467,000	620,000
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	33,577,000	(36,594,000)	88,123,000	(43,447,000)
Income Tax Expense (Benefit)	9,079,000	(10,416,000)	28,028,000	(202,000)
Net Income (Loss) Attributable to Parent	24,498,000	(26,178,000)	60,095,000	(43,245,000)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(661,000)	849,000	(1,349,000)	(1,381,000)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent	0	1,000	0	(14,000)
Other Comprehensive Income (Loss), Net of Tax	(661,000)	850,000	(1,349,000)	(1,395,000)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 23,837,000	$ (25,328,000)	$ 58,746,000	$ (44,640,000)
Weighted Average Number of Shares Outstanding, Basic	19,569,000	19,351,000	19,489,000	19,281,000
Weighted Average Number of Shares Outstanding, Diluted	20,240,000	19,351,000	20,259,000	19,281,000
Earnings Per Share, Basic	$ 1.25	$ (1.35)	$ 3.08	$ (2.24)
Earnings Per Share, Diluted	1.21	(1.35)	2.97	(2.24)
Common Stock, Dividends, Per Share, Declared	$ 0.15	$ 0.15	$ 0.45	$ 0.45
Restructuring Charges	$ (3,262,000)	$ 48,115,000	$ 3,792,000	$ 48,115,000
Reimbursements
Revenue from Contract with Customer, Excluding Assessed Tax	1,490,000	957,000	3,819,000	6,555,000
Cost of Goods and Services Sold	1,490,000	957,000	3,819,000	6,555,000
Cost of Services
Cost of Goods and Services Sold	$ 18,686,000	$ 870,000	$ 34,817,000	$ 2,848,000

Statement of Shareholders' Equi

Statement of Shareholders' Equity (Statement) - USD ($)	Total	Common Stock Including Additional Paid in Capital	Treasury Stock	Additional Paid-in Capital	Retained Earnings	AOCI Attributable to Parent	Common Stock	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, AdjustmentRetained Earnings
Common Stock, Shares, Outstanding		19,586,000	420,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 309,115,000	$ 196,000	$ (14,795,000)	$ 228,807,000	$ 91,083,000	$ 3,824,000
Net Income (Loss) Attributable to Parent	8,666,000				8,666,000
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	2,614,000			2,614,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	(1,550,000)		$ 3,838,000	(5,388,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(109,000)
Dividends, Cash	(2,876,000)				(2,876,000)
Dividend, Share-based Payment Arrangement, Cash	$ (126,000)				(126,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ (3,746,000)					(3,746,000)
Net Income (Loss) Attributable to Parent	(43,245,000)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(44,640,000)
Other Comprehensive Income (Loss), Net of Tax	(1,395,000)
Common Stock, Shares, Outstanding		19,586,000	311,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	311,765,000	$ 196,000	$ (10,957,000)	226,033,000	96,415,000	78,000
Stockholders' Equity Attributable to Parent								$ (332,000)	$ (332,000)
Net Income (Loss) Attributable to Parent	(25,733,000)				(25,733,000)
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	1,320,000			1,320,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	0		$ 1,685,000	(1,685,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(48,000)
Dividends, Cash	(2,891,000)				(2,891,000)
Stock Issued During Period, Shares, Treasury Stock Reissued			(15,000)
Stock Issued During Period, Value, Treasury Stock Reissued	346,000		$ 529,000	(183,000)
Dividend, Share-based Payment Arrangement, Cash	$ (105,000)				(105,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ 1,501,000					1,501,000
Common Stock, Shares, Outstanding		19,586,000	248,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	286,203,000	$ 196,000	$ (8,743,000)	225,485,000	67,686,000	1,579,000
Net Income (Loss) Attributable to Parent	(26,178,000)				(26,178,000)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(25,328,000)
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	3,212,000			3,212,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings			$ 702,000	(702,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(22,000)
Dividends, Cash	(2,905,000)				(2,905,000)
Dividend, Share-based Payment Arrangement, Cash	$ (116,000)				(116,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ 850,000					850,000
Common Stock, Shares, Outstanding		19,586,000	226,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 261,066,000	$ 196,000	$ (8,041,000)	227,995,000	38,487,000	2,429,000
Common Stock, Shares, Outstanding	19,359,586	19,586,000	226,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 267,602,000	$ 196,000	$ (8,041,000)	231,048,000	40,982,000	3,417,000
Net Income (Loss) Attributable to Parent	14,832,000				14,832,000
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	2,991,000			2,991,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	(3,090,000)		$ 4,951,000	(8,041,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(138,000)
Dividends, Cash	(2,905,000)				(2,905,000)
Dividend, Share-based Payment Arrangement, Cash	$ (167,000)				(167,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ (693,000)					(693,000)
Net Income (Loss) Attributable to Parent	60,095,000
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	58,746,000
Other Comprehensive Income (Loss), Net of Tax	(1,349,000)
Common Stock, Shares, Outstanding		19,586,000	88,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	278,570,000	$ 196,000	$ (3,090,000)	225,998,000	52,742,000	2,724,000
Net Income (Loss) Attributable to Parent	20,765,000				20,765,000
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	2,861,000			2,861,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	0		$ 808,000	(808,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(23,000)
Dividends, Cash	(2,926,000)				(2,926,000)
Stock Issued During Period, Shares, Treasury Stock Reissued			(9,000)
Stock Issued During Period, Value, Treasury Stock Reissued	345,000		$ 280,000	65,000
Dividend, Share-based Payment Arrangement, Cash	$ (67,000)				(67,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ 5,000					5,000
Common Stock, Shares, Outstanding		19,586,000	56,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	299,553,000	$ 196,000	$ (2,002,000)	228,116,000	70,514,000	2,729,000
Net Income (Loss) Attributable to Parent	24,498,000				24,498,000
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	23,837,000
APIC, Share-based Payment Arrangement, Restricted Stock Unit, Increase for Cost Recognition	2,820,000			2,820,000
Restricted Stock, Value, Shares Issued Net of Tax Withholdings	0		$ 1,821,000	(1,821,000)
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			(51,000)				11,000
Dividends, Cash	(2,939,000)				(2,939,000)
Dividend, Share-based Payment Arrangement, Cash	$ (15,000)				(15,000)
Common Stock, Dividends, Per Share, Declared	$ 0.15
Other Comprehensive Income (Loss), Net of Tax	$ (661,000)					(661,000)
Common Stock, Shares, Outstanding	19,591,527	19,597,000	5,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 323,256,000	$ 196,000	$ (181,000)	$ 229,115,000	$ 92,058,000	$ 2,068,000

Statement of Cash Flows (Statem

Statement of Cash Flows (Statement) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Statement of Cash Flows [Abstract]
Net Income (Loss) Attributable to Parent	$ 60,095,000	$ (43,245,000)
Depreciation, Depletion and Amortization	16,576,000	20,638,000
Deferred Income Tax Expense (Benefit)	(1,486,000)	700,000
Share-based Payment Arrangement, Noncash Expense	8,672,000	7,146,000
Accretion Expense	363,000	0
Marketable Securities, Gain (Loss)	(1,000)	(144,000)
Gain (Loss) on Disposition of Assets	127,000	289,000
Asset Impairment Charges	0	32,970,000
Increase (Decrease) in Accounts Receivable	(84,877,000)	(9,616,000)
Increase (Decrease) in Accounts Payable	2,931,000	2,809,000
Increase (Decrease) in Accrued Liabilities	89,405,000	(77,776,000)
Restructuring Reserve, Accrual Adjustment	(5,024,000)	6,289,000
Increase (Decrease) in Deferred Revenue	6,453,000	(3,892,000)
Increase (Decrease) in Income Taxes Payable, Net of Income Taxes Receivable	14,937,000	(11,460,000)
Increase (Decrease) in Obligation, Pension Benefits	1,443,000	1,304,000
Increase (Decrease) in Prepaid Expense	(7,724,000)	(1,229,000)
Increase (Decrease) in Other Operating Assets and Liabilities, Net	(37,114,000)	2,312,000
Net Cash Provided by (Used in) Operating Activities	64,776,000	(72,905,000)
Payments to Acquire Businesses, Gross	(31,969,000)	0
Payments to Acquire Property, Plant, and Equipment	(3,902,000)	(7,121,000)
Payments to Acquire Available-for-sale Securities	(1,997,000)	(118,668,000)
Proceeds from Sale of Debt Securities, Available-for-sale	20,653,000	111,633,000
Net Cash Provided by (Used in) Investing Activities	(17,215,000)	(14,156,000)
Proceeds from Lines of Credit	0	100,000,000
Repayments of Lines of Credit	0	(100,000,000)
Payments of Dividends	(8,927,000)	(9,019,000)
Payment, Tax Withholding, Share-based Payment Arrangement	(3,090,000)	(1,550,000)
Payment for Contingent Consideration Liability, Financing Activities	0	(2,789,000)
Net Cash Provided by (Used in) Financing Activities	(12,017,000)	(13,358,000)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	(3,707,000)	(723,000)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	31,837,000	(101,142,000)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	348,326,000	170,577,000
Payments to Acquire Property, Plant, and Equipment	3,902,000	7,121,000
Payments to Acquire Available-for-sale Securities	1,997,000	118,668,000
Net Cash Provided by (Used in) Investing Activities	(17,215,000)	(14,156,000)
Proceeds from Lines of Credit	0	100,000,000
Payments of Dividends	8,927,000	9,019,000
Payment, Tax Withholding, Share-based Payment Arrangement	3,090,000	1,550,000
Payment for Contingent Consideration Liability, Financing Activities	0	2,789,000
Net Cash Provided by (Used in) Financing Activities	(12,017,000)	(13,358,000)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	(3,707,000)	(723,000)
Net Income (Loss) Attributable to Parent	60,095,000	(43,245,000)
Depreciation, Depletion and Amortization	16,576,000	20,638,000
Deferred Income Tax Expense (Benefit)	(1,486,000)	700,000
Share-based Payment Arrangement, Noncash Expense	8,672,000	7,146,000
Accretion Expense	363,000	0
Marketable Securities, Gain (Loss)	1,000	144,000
Gain (Loss) on Disposition of Assets	(127,000)	(289,000)
Asset Impairment Charges	0	32,970,000
Increase (Decrease) in Accounts Receivable	84,877,000	9,616,000
Increase (Decrease) in Accounts Payable	2,931,000	2,809,000
Increase (Decrease) in Accrued Liabilities	89,405,000	(77,776,000)
Restructuring Reserve, Accrual Adjustment	(5,024,000)	6,289,000
Increase (Decrease) in Deferred Revenue	6,453,000	(3,892,000)
Increase (Decrease) in Income Taxes Payable, Net of Income Taxes Receivable	14,937,000	(11,460,000)
Increase (Decrease) in Obligation, Pension Benefits	1,443,000	1,304,000
Increase (Decrease) in Prepaid Expense	7,724,000	1,229,000
Increase (Decrease) in Other Operating Assets and Liabilities, Net	37,114,000	(2,312,000)
Net Cash Provided by (Used in) Operating Activities	64,776,000	(72,905,000)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	31,837,000	(101,142,000)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 348,326,000	$ 170,577,000

Statement of Financial Positi_2

Statement of Financial Position, Classified (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares, Outstanding	19,591,527	19,359,586
Treasury Stock, Shares	5,080	226,191
Accounts Receivable, Allowance for Credit Loss, Current	$ 7,562,000	$ 6,557,000
Common Stock, Shares, Issued	19,596,607	19,585,777

Organization, Consolidation and

Organization, Consolidation and Presentation of Financial Statements	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure	The accompanying unaudited Condensed Consolidated Financial Statements of Heidrick & Struggles International, Inc. and subsidiaries (the "Company") have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission ("SEC"). The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses. Significant items subject to estimates and assumptions include revenue recognition, income taxes, interim effective tax rate and the assessment of goodwill, other intangible assets and long lived assets for impairment. Estimates are subject to a degree of uncertainty and actual results could differ from these estimates. In the opinion of management, all adjustments necessary to fairly present the financial position of the Company at September 30, 2021 and December 31, 2020, the results of operations for the three and nine months ended September 30, 2021 and 2020 and its cash flows for the nine months ended September 30, 2021 and 2020 have been included and are of a normal, recurring nature except as otherwise disclosed. These financial statements and notes are to be read in conjunction with the Company’s Consolidated Financial Statements and Notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC on February 24, 2021.

Accounting Policies

Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	A complete listing of the Company’s significant accounting policies is discussed in Note 2, Summary of Significant Accounting Policies , in the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. Revenue Recognition See Note 3 , Revenue. Cost of Services Cost of services consists of third-party contractor costs related to the delivery of various services in the Company's On-Demand Talent and Heidrick Consulting operating segments. Marketable Securities The Company’s marketable securities consist of available-for-sale debt securities with original maturities exceeding three months. Restricted Cash The following table provides a reconciliation of the cash and cash equivalents between the Condensed Consolidated Balance Sheets and the Condensed Consolidated Statements of Cash Flows as of September 30, 2021 and 2020, and December 31, 2020 and 2019: September 30, December 31, 2021 2020 2020 2019 Cash and cash equivalents $ 348,292 $ 170,577 $ 316,473 $ 271,719 Restricted cash included within other non-current assets 34 — 16 — Total cash, cash equivalents and restricted cash $ 348,326 $ 170,577 $ 316,489 $ 271,719 Earnings (Loss) per Common Share Basic earnings (loss) per common share is computed by dividing net income (loss) by weighted average common shares outstanding for the period. Diluted earnings (loss) per share reflect the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted. Common equivalent shares are excluded from the determination of diluted earnings (loss) per share in periods in which they have an anti-dilutive effect. The following table sets forth the computation of basic and diluted earnings (loss) per share: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Net income (loss) $ 24,498 $ (26,178) $ 60,095 $ (43,245) Weighted average shares outstanding: Basic 19,569 19,351 19,489 19,281 Effect of dilutive securities: Restricted stock units 524 — 584 — Performance stock units 147 — 186 — Diluted 20,240 19,351 20,259 19,281 Basic earnings (loss) per share $ 1.25 $ (1.35) $ 3.08 $ (2.24) Diluted earnings (loss) per share $ 1.21 $ (1.35) $ 2.97 $ (2.24) Weighted average restricted stock units and performance stock units outstanding that could be converted into approximately 315,000 and 63,000 common shares, respectively, for the three months ended September 30, 2020, and 454,000 and 98,000 common shares, respectively, for the nine months ended September 30, 2020, were not included in the computation of diluted earnings (loss) per share because the effects would be anti-dilutive. Reclassifications Certain prior year amounts have been recast as a result of the Company's presentation of Cost of services in the Condensed Consolidated Statements of Comprehensive Income (Loss). The reclassifications had no impact on net income (loss), net cash flows or stockholders' equity. Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in Operating Lease Right-of-Use Assets , Operating Lease Liabilities - Current and Operating Lease Liabilities - Non-Current in our Condensed Consolidated Balance Sheets. The Company does not have any leases that meet the finance lease criteria. Right-of-use assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized on the commencement date based on the present value of lease payments over the lease term. As most of the Company's leases do not provide an implicit rate, an incremental borrowing rate based on the information available at the commencement date is used in determining the present value of lease payments. The operating lease right-of-use asset also includes any lease payments made in advance and any accrued rent expense balances. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components. For office leases, the Company accounts for the lease and non-lease components as a single lease component. For equipment leases, such as vehicles and office equipment, the Company accounts for the lease and non-lease components separately. Recently Issued Financial Accounting Standards In March 2020, the Financial Accounting Standards Board issued Accounting Standards Update ("ASU") No. 2020-04, Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The guidance is intended to provide temporary optional expedients and exceptions to the guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates. This guidance is effective March 12, 2020, and the Company may elect to apply the amendments prospectively through December 31, 2022. The Company is currently evaluating the impact of this accounting guidance. The effect is not known or reasonably estimable at this time. Recently Adopted Financial Accounting Standards On January 1, 2021, the Company adopted ASU No. 2019-12, Simplifying the Accounting for Income Taxes. The guidance simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in Accounting Standards Codification ("ASC") 740 related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The guidance also simplifies aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The adoption had no impact on the Condensed Consolidated Statements of Comprehensive Income (Loss), Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Cash Flows and Condensed Consolidated Statements of Changes in Stockholders' Equity in any period presented.

Revenue from Contract with Cust

Revenue from Contract with Customer	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer	Executive Search Revenue is recognized as performance obligations are satisfied by transferring a good or service to a client. Generally, each executive search contract contains one performance obligation which is the process of identifying potentially qualified candidates for a specific client position. In most contracts, the transaction price includes both fixed and variable consideration. Fixed compensation is comprised of a retainer, equal to approximately one-third of the estimated first year compensation for the position to be filled, and indirect expenses, equal to a specified percentage of the retainer, as defined in the contract. The Company generally bills clients for the retainer and indirect expenses in one-third increments over a three-month period commencing in the month of a client’s acceptance of the contract. If actual compensation of a placed candidate exceeds the original compensation estimate, the Company is often authorized to bill the client for one-third of the excess compensation. The Company refers to this additional billing as uptick revenue. In most contracts, variable consideration is comprised of uptick revenue and direct expenses. The Company bills its clients for uptick revenue upon completion of the executive search, and direct expenses are billed as incurred. The Company estimates uptick revenue at contract inception, based on a portfolio approach, utilizing the expected value method based on a historical analysis of uptick revenue realized in the Company’s geographic regions and industry practices, and initially records a contract’s uptick revenue in an amount that is probable not to result in a significant reversal of cumulative revenue recognized when the actual amount of uptick revenue for the contract is known. Differences between the estimated and actual amounts of variable consideration are recorded when known. The Company does not estimate revenue for direct expenses as it is not materially different than recognizing revenue as direct expenses are incurred. Revenue from executive search engagement performance obligations is recognized over time as clients simultaneously receive and consume the benefits provided by the Company's performance. Revenue from executive search engagements is recognized over the expected average period of performance, in proportion to the estimated personnel time incurred to fulfill the obligations under the executive search contract. Revenue is generally recognized over a period of approximately six months. The Company's executive search contracts contain a replacement guarantee which provides for an additional search to be completed, free of charge except for expense reimbursements, should the candidate presented by the Company be hired by the client and subsequently terminated by the client for performance reasons within a specified period of time. The replacement guarantee is an assurance warranty, which is not a performance obligation under the terms of the executive search contract, as the Company does not provide any services under the terms of the guarantee that transfer benefits to the client in excess of assuring that the identified candidate complies with the agreed-upon specifications. The Company accounts for the replacement guarantee under the relevant warranty guidance in ASC 460 - Guarantees. Heidrick Consulting Revenue is recognized as performance obligations are satisfied by transferring a good or service to a client. Heidrick Consulting enters into contracts with clients that outline the general terms and conditions of the assignment to provide succession planning, executive assessment, top team and board effectiveness and culture shaping programs. The consideration the Company expects to receive under each contract is generally fixed. Most of the Company's consulting contracts contain one performance obligation, which is the overall process of providing the consulting service requested by the client. The majority of our consulting revenue is recognized over time utilizing both input and output methods. Contracts that contain coaching sessions, training sessions or the completion of assessments are recognized using the output method as each session or assessment is delivered to the client. Contracts that contain general consulting work are recognized using the input method utilizing a measure of progress that is based on time incurred on the project. The Company enters into enterprise agreements with clients to provide a license for online access, via the Company's Culture Connect platform, to training and other proprietary material related to the Company's culture shaping programs. The consideration the Company expects to receive under the terms of an enterprise agreement is comprised of a single fixed fee. The enterprise agreements contain multiple performance obligations, the delivery of materials via Culture Connect and material rights related to options to renew enterprise agreements at a significant discount. The Company allocates the transaction price to the performance obligations in the contract on a stand-alone selling price basis. The stand-alone selling price for the initial term of the enterprise agreement is outlined in the contract and is equal to the price paid by the client for the agreement over the initial term of the contract. The stand-alone selling price for the options to renew, or material right, are not directly observable and must be estimated. This estimate is required to reflect the discount the client would obtain when exercising the option to renew, adjusted for the likelihood that the option will be exercised. The Company estimates the likelihood of renewal using a historical analysis of client renewals. Access to Culture Connect represents a right to access the Company’s intellectual property that the client simultaneously receives and consumes as the Company performs under the agreement, and therefore the Company recognizes revenue over time. Given the continuous nature of this commitment, the Company utilizes straight-line ratable revenue recognition over the estimated subscription period as the Company's clients will receive and consume the benefits from Culture Connect equally throughout the contract period. Revenue related to client renewals of enterprise agreements is recognized over the term of the renewal, which is generally twelve months. Enterprise agreements do not comprise a significant portion of the Company's revenue. On-Demand Talent The Company enters into contracts with clients that outline the general terms and conditions of the assignment to provide on-demand consultants for various types of consulting projects, which consultants may be independent contractors or temporary employees. The consideration the Company expects to receive under each contract is dependent on the time-based fees specified in the contract. Revenue from on-demand engagement performance obligations is recognized over time as clients simultaneously receive and consume the benefits provided by the Company's performance. The Company has applied the practical expedient to recognize revenue for these services in the amount to which the Company has a right to invoice the client, as this amount corresponds directly with the value provided to the client for the performance completed to date. For transactions where a third-party contractor is involved in providing the services to the client, the Company reports the revenue and the related direct costs on a gross basis as it has determined that it is the principal in the transaction. The Company is primarily responsible for fulfilling the promise to provide consulting services to its clients and the Company has discretion in establishing the prices charged to clients for the consulting services and is able to contractually obligate the independent service provider to deliver services and deliverables that the Company has agreed to provide to its clients. Contract Balances Contract assets and liabilities are reported in a net position on a contract-by-contract basis at the end of each reporting period. Contract assets and liabilities are classified as current due to the nature of the Company's contracts, which are completed within one year. Contract assets are included within Other Current Assets on the Condensed Consolidated Balance Sheets. Unbilled receivables: Unbilled revenue represents contract assets from revenue recognized over time in excess of the amount billed to the client and the amount billed to the client is solely dependent upon the passage of time. This amount includes revenue recognized in excess of billed executive search retainers, Heidrick Consulting fees, and On-Demand Talent fees. Contract assets: Contract assets represent revenue recognized over time in excess of the amount billed to the client and the amount billed to the client is not solely subject to the passage of time. This amount primarily includes revenue recognized for upticks and contingent placement fees in executive search contracts. Deferred revenue: Contract liabilities consist of deferred revenue, which is equal to billings in excess of revenue recognized. The following table outlines the changes in the contract asset and liability balances from December 31, 2020 to September 30, 2021: September 30, December 31, Change Contract assets Unbilled receivables, net $ 16,584 $ 9,907 $ 6,677 Contract assets 13,886 9,745 4,141 Total contract assets 30,470 19,652 10,818 Contract liabilities Deferred revenue $ 45,284 $ 38,050 $ 7,234 During the nine months ended September 30, 2021, the Company recognized revenue of $33.6 million that was included in the contract liabilities balance at the beginning of the period. The amount of revenue recognized during the nine months ended September 30, 2021, from performance obligations partially satisfied in previous periods as a result of changes in the estimates of variable consideration was $26.0 million. Each of the Company's contracts has an expected duration of one year or less.

Credit Losses

Credit Losses	9 Months Ended
	Sep. 30, 2021
Credit Loss [Abstract]
Loans, Notes, Trade and Other Receivables Disclosure	The Company is exposed to credit losses primarily through the provision of its executive search, consulting, and on-demand talent services. The Company’s expected credit loss allowance methodology for accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of clients' trade accounts receivables. Due to the short-term nature of such receivables, the estimate of amount of accounts receivable that may not be collected is primarily based on historical loss-rate experience. When required, the Company adjusts the loss-rate methodology to account for current conditions and reasonable and supportable expectations of future economic and market conditions. The Company generally assesses future economic conditions for a period of sixty to ninety days, which corresponds with the contractual life of its accounts receivables. Additionally, specific allowance amounts are established to record the appropriate provision for clients that have a higher probability of default. The Company’s monitoring activities include timely account reconciliation, dispute resolution, payment confirmation, consideration of clients' financial condition and macroeconomic conditions. Balances are written off when determined to be uncollectible. The Company considered the current and expected future economic and market conditions surrounding the COVID-19 pandemic and determined that the estimate of credit losses was not significantly impacted. The activity in the allowance for credit losses on the Company's trade receivables is as follows: Balance at December 31, 2020 $ 6,557 Provision for credit losses 4,622 Write-offs (3,523) Foreign currency translation (94) Balance at September 30, 2021 $ 7,562 The fair value and unrealized losses on available for sale debt securities, aggregated by investment category and the length of time the security has been in an unrealized loss position, are as follows: Less Than 12 Months Balance Sheet Classification Balance at September 30, 2021 Fair Value Unrealized Loss Cash and Cash Equivalents Marketable Securities U.S. Treasury securities $ 36,198 $ 1 $ 36,198 $ — Less Than 12 Months Balance Sheet Classification Balance at December 31, 2020 Fair Value Unrealized Loss Cash and Cash Equivalents Marketable Securities U.S. Treasury securities $ 31,997 $ 1 $ 31,997 $ —

Property, Plant, and Equipment

Property, Plant, and Equipment	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure	The components of the Company’s property and equipment are as follows: September 30, December 31, Leasehold improvements $ 35,980 $ 40,320 Office furniture, fixtures and equipment 13,858 14,816 Computer equipment and software 24,714 25,544 Property and equipment, gross 74,552 80,680 Accumulated depreciation (53,613) (57,188) Property and equipment, net $ 20,939 $ 23,492 Depreciation expense for the three months ended September 30, 2021 and 2020 was $1.8 million and $2.1 million, respectively. Depreciation expense for the nine months ended September 30, 2021 and 2020 was $5.3 million and $6.2 million, respectively.

Leases, Codification Topic 842

Leases, Codification Topic 842	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Lessee, Operating Leases	The Company's lease portfolio is comprised of operating leases for office space and equipment. The majority of the Company's leases include both lease and non-lease components, which the Company accounts for differently depending on the underlying class of asset. Certain of the Company's leases include one or more options to renew or terminate the lease at the Company's discretion. Generally, the renewal and termination options are not included in the right-of-use assets and lease liabilities as they are not reasonably certain of exercise. The Company regularly evaluates the renewal and termination options and when they are reasonably certain of exercise, includes the renewal or termination option in the lease term. As most of the Company's leases do not provide an implicit interest rate, the Company utilizes an incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company has a centrally managed treasury function and therefore, a portfolio approach is applied in determining the incremental borrowing rate. The incremental borrowing rate is the rate of interest that the Company would have to pay to borrow on a fully collateralized basis over a similar term in an amount equal to the total lease payments in a similar economic environment. Office leases have remaining lease terms that range from less than one year to 11.8 years, some of which also include options to extend or terminate the lease. Most office leases contain both fixed and variable lease payments. Variable lease costs consist primarily of rent escalations based on an established index or rate and taxes, insurance, and common area or other maintenance costs, which are paid based on actual costs incurred by the lessor. The Company has elected to utilize the available practical expedient to not separate lease and non-lease components for office leases. Under the Company's restructuring plan, a lease component related to one of the Company's offices was abandoned and the useful life of the associated right-of-use asset was shortened to correspond with the cease-use date. As a result of the change in useful life, approximately $8.7 million and $1.2 million of right-of-use asset amortization was accelerated and recorded in Restructuring charges in the Condensed Consolidated Statements of Comprehensive Income (Loss) and Depreciation and amortization in the Condensed Consolidated Statements of Cash Flows during the three and nine months ended September 30, 2021, respectively. Approximately $10.6 million of right-of-use asset amortization was accelerated and recorded in Restructuring charges in the Condensed Consolidated Statements of Comprehensive Income (Loss) and Depreciation and amortization in the Condensed Consolidated Statements of Cash Flows during the three and nine months ended September 30, 2020. In September 2021, the Company entered into a termination and surrender agreement for this lease component. Under the terms of the agreement, the Company made a one-time payment of $11.7 million to release the Company from all remaining obligations under the lease. At the time of payment, the Company had accrued approximately $17.4 million of lease liabilities related to future payments under the remaining lease term. Upon making the one-time payment, the lease liabilities were relieved, resulting in a gain on termination of approximately $5.7 million, which is recorded in Restructuring charges in the Condensed Consolidated Statements of Comprehensive Income (Loss) for the three and nine months ended September 30, 2021. Equipment leases, which are comprised of vehicle and office equipment leases, have remaining terms that range from less than one year to 4.5 years, some of which also include options to extend or terminate the lease. The Company's equipment leases do not contain variable lease payments. The Company separates the lease and non-lease components for its equipment leases. Equipment leases do not comprise a significant portion of the Company's lease portfolio. Lease cost components included within General and Administrative Expenses in our Condensed Consolidated Statements of Comprehensive Income (Loss) were as follows: Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Operating lease cost $ 4,682 $ 6,241 $ 14,457 $ 18,688 Variable lease cost 1,480 1,048 3,785 4,832 Total lease cost $ 6,162 $ 7,289 $ 18,242 $ 23,520

Fair Value Measures and Disclos

Fair Value Measures and Disclosures	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Investment	Cash, Cash Equivalents and Marketable Securities The Company's investments in marketable debt securities, which consist of U.S. Treasury bills, are classified and accounted for as available-for-sale. The Company classifies its marketable debt securities as either short-term or long-term based on each instrument's underlying contractual maturity date. Unrealized gains and losses on marketable debt securities classified as available-for-sale are recognized in Accumulated other comprehensive income in the Condensed Consolidated Balance Sheets until realized. The Company's cash, cash equivalents, and marketable securities by significant investment category are as follows: Cash and Cash Equivalents Balance at September 30, 2021 Cash $ 165,934 Level 1 (1) : Money market funds 80,161 U.S. Treasury securities 102,197 Total Level 1 182,358 Total $ 348,292 Fair Value Balance Sheet Classification Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Balance at December 31, 2020 Cash $ 230,490 $ — Level 1 (1) : Money market funds 53,986 — U.S. Treasury securities $ 51,996 $ 1 $ (1) $ 51,996 31,997 19,999 Total Level 1 51,996 1 (1) 51,996 85,983 19,999 Total $ 51,996 $ 1 $ (1) $ 51,996 $ 316,473 $ 19,999 (1) Level 1 – Quoted prices in active markets for identical assets and liabilities. Investments, Assets Designated for Retirement and Pension Plans and Associated Liabilities The Company has a U.S. non-qualified deferred compensation plan that consists primarily of U.S. marketable securities and mutual funds. The aggregate cost basis for these investments was $21.2 million and $19.5 million as of September 30, 2021 and December 31, 2020, respectively. The Company also maintains a pension plan for certain current and former employees in Germany. The pensions are individually fixed Euro amounts that vary depending on the function and the eligible years of service of the employee. The Company’s investment strategy is to support its pension obligations through reinsurance contracts. The BaFin—German Federal Financial Supervisory Authority—supervises the insurance companies and the reinsurance contracts. The BaFin requires each reinsurance contract to guarantee a fixed minimum return. The Company’s pension benefits are fully reinsured by group insurance contracts with ERGO Lebensversicherung AG, and the group insurance contracts are measured in accordance with BaFin guidelines (including mortality tables and discount rates) which are considered Level 2 inputs. The following tables provide a summary of the fair value measurements for each major category of investments, assets designated for retirement and pension plans and associated liabilities measured at fair value: Balance Sheet Classification Fair Value Other Current Assets Assets Designated for Retirement and Pension Plans Investments Other Current Liabilities Retirement and Pension Plans Balance at September 30, 2021 Measured on a recurring basis: Level 1 (1) : U.S. non-qualified deferred compensation plan $ 34,738 $ — $ — $ 34,738 $ — $ — Level 2 (2) : Retirement and pension plan assets 15,031 1,359 13,672 — — — Pension benefit obligation (21,184) — — — (1,359) (19,825) Total Level 2 (6,153) 1,359 13,672 — (1,359) (19,825) Total $ 28,585 $ 1,359 $ 13,672 $ 34,738 $ (1,359) $ (19,825) Balance Sheet Classification Fair Value Other Current Assets Goodwill Assets Designated for Retirement and Pension Plans Investments Other Current Liabilities Retirement and Pension Plans Balance at December 31, 2020 Measured on a recurring basis: Level 1 (1) : U.S. non-qualified deferred compensation plan $ 31,369 $ — $ — $ — $ 31,369 $ — $ — Level 2 (2) : Retirement and pension plan assets 15,859 1,434 — 14,425 — — — Pension benefit obligation (22,351) — — — — (1,434) (20,917) Total Level 2 (6,492) 1,434 — 14,425 — (1,434) (20,917) Measured on a non-recurring basis: Level 3 (3)(4) : Goodwill 91,643 91,643 Total $ 116,520 $ 1,434 $ 91,643 $ 14,425 $ 31,369 $ (1,434) $ (20,917) (1) Level 1 – Quoted prices in active markets for identical assets and liabilities. (2) Level 2 – Quoted prices in active markets for similar assets and liabilities, or other inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument. (3) Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs. (4) In accordance with Subtopic 350-20, goodwill with a carrying value of $33.0 million was written down to its implied fair value of zero during the three months ended June 30, 2020, resulting in the revised total goodwill of $91.6 million and an impairment charge of $33.0 million in earnings. Contingent Consideration and Compensation The former owners of the Company's acquisitions are eligible to receive additional cash compensation based on the attainment of certain operating metrics in the periods subsequent to acquisition. Contingent consideration and compensation are valued using significant inputs that are not observable in the market, which are defined as Level 3 inputs pursuant to fair value measurement accounting. The Company determines the fair value of contingent consideration and compensation using discounted cash flow models. The following table provides a reconciliation of the beginning and ending balance of Level 3 liabilities for the nine months ended September 30, 2021: Earnout Contingent Compensation Balance at December 31, 2020 $ — $ (2,390) Acquisition earnout (See Note 8, Acquisitions ) (23,800) — Earnout accretion (363) — Compensation expense — (1,398) Foreign currency translation — 139 Balance at September 30, 2021 $ (24,163) $ (3,649) Earnout accruals and contingent compensation accruals are recorded within Other non-current liabilities and non-current Accrued salaries and benefits, respectively, in the Condensed Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets Disclosure	Goodwill The Company's goodwill by segment is as follows: September 30, December 31, Executive Search Americas $ 91,518 $ 91,643 Total Executive Search 91,518 91,643 On-Demand Talent 45,529 — Total goodwill $ 137,047 $ 91,643 Changes in the carrying amount of goodwill by segment for the nine months ended September 30, 2021, are as follows: Executive Search On-Demand Talent Americas Europe Asia Pacific Total Goodwill $ 91,643 $ 24,475 $ 8,495 $ — $ 124,613 Accumulated impairment losses — (24,475) (8,495) — (32,970) Balance at December 31, 2020 91,643 — — — 91,643 BTG acquisition — — — 45,529 45,529 Foreign currency translation (125) — — — (125) Balance at September 30, 2021 $ 91,518 $ — $ — $ 45,529 $ 137,047 In April 2021, the Company acquired BTG and included $45.5 million of goodwill related to the acquisition in the On-Demand Talent operating segment. Other Intangible Assets, net The Company’s other intangible assets, net by segment, are as follows: September 30, December 31, Executive Search Americas $ 122 $ 225 Europe 544 852 Asia Pacific 37 52 Total Executive Search 703 1,129 On-Demand Talent 9,520 — Total other intangible assets, net $ 10,223 $ 1,129 In April 2021, the Company acquired BTG and recorded customer relationships, software and trade name intangible assets in the On-Demand Talent operating segment of $5.8 million, $3.1 million and $1.7 million, respectively. The combined weighted-average amortization period for the acquired intangible assets is 7.4 years with amortization periods of 11.0, 3.0 and 3.0 years for the customer relationships, software and trade name, respectively. The carrying amount of amortizable intangible assets and the related accumulated amortization are as follows: Weighted September 30, 2021 December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Client relationships 10.5 $ 22,144 $ (16,000) $ 6,144 $ 16,600 $ (15,587) $ 1,013 Trade name 3.1 2,445 (958) 1,487 280 (164) 116 Software 3.0 3,110 (518) 2,592 — — — Total intangible assets 7.5 $ 27,699 $ (17,476) $ 10,223 $ 16,880 $ (15,751) $ 1,129 Intangible asset amortization expense for the three months ended September 30, 2021 and 2020 was $0.8 million and $0.2 million, respectively. Intangible amortization expense for the nine months ended September 30, 2021 and 2020 was $1.8 million and $0.6 million, respectively. The Company's estimated future amortization expense related to intangible assets as of September 30, 2021, for the years ended December 31 is as follows: 2021 $ 626 2022 2,763 2023 2,885 2024 1,346 2025 801 Thereafter 1,802 Total $ 10,223

Deferred Costs, Capitalized, Pr

Deferred Costs, Capitalized, Prepaid, and Other Assets	9 Months Ended
	Sep. 30, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Additional Financial Information Disclosure	The components of other current assets are as follows: September 30, December 31, Contract assets $ 30,470 $ 19,652 Other 3,977 3,627 Total other current assets $ 34,447 $ 23,279

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt Disclosure	On July 13, 2021, the Company entered into a First Amendment to the 2018 Credit Agreement (the "Amendment"). The Amendment provides the Company with a committed unsecured revolving credit facility in an aggregate amount of $200 million, increased from $175 million as set forth in the 2018 Credit Agreement, which includes a sublimit of $25 million for letters of credit and a sublimit of $10 million for swingline loans, with a $75 million expansion feature. The Amendment matures on July 13, 2026, extended from October 26, 2023 as set forth in the 2018 Credit Agreement. Borrowings under the Amendment may be used for working capital, capital expenditures, permitted acquisitions, restricted payments and for other general corporate purposes of the Company and its subsidiaries. The obligations under the Amendment are guaranteed by certain of the Company’s subsidiaries. During the three months ended March 31, 2020, the Company borrowed $100.0 million under the 2018 Credit Agreement. The Company elected to draw down a portion of the available funds from its revolving line of credit as a precautionary measure to increase its cash position and further enhance its financial flexibility in light of the uncertainty in global markets resulting from the COVID-19 outbreak. The Company subsequently repaid $100.0 million during the three months ended September 30, 2020. As of September 30, 2021 and December 31, 2020, the Company had no outstanding borrowings. The Company was in compliance with the financial and other covenants under the Amendment and no event of default existed.

Compensation Related Costs, Sha

Compensation Related Costs, Share Based Payments	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement	On May 28, 2020, the stockholders of the Company approved an amendment to the Company's Second Amended and Restated 2012 Heidrick & Struggles GlobalShare Program (as so amended, the "Third A&R 2012 Program") to increase the number of shares of Common Stock reserved for issuance under the 2012 Program by 500,000 shares. The Third A&R 2012 Program provides for grants of stock options, stock appreciation rights, and other stock-based compensation awards that are valued based upon the grant date fair value of shares. These awards may be granted to directors, selected employees and independent contractors. As of September 30, 2021, 3,369,759 awards have been issued under the Third A&R 2012 Program, including 742,624 forfeited awards, and 722,865 shares remain available for future awards. The Third A&R 2012 Program provides that no awards can be granted after May 28, 2028. The Company measures its stock-based compensation costs based on the grant date fair value of the awards and recognizes these costs over the requisite service period. A summary of information with respect to stock-based compensation is as follows: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Salaries and benefits (1) $ 3,321 $ 3,850 $ 14,552 $ 6,645 General and administrative expenses — — 345 460 Income tax benefit related to stock-based compensation included in net income (loss) 886 1,022 3,976 1,886 (1) Includes $0.5 million and $0.7 million of expense related to cash settled restricted stock units for the three months ended September 30, 2021 and 2020, respectively, and $6.2 million and less than $0.1 million of expense related to cash settled restricted stock units for the nine months ended September 30, 2021 and 2020, respectively. Restricted Stock Units Restricted stock units are generally subject to ratable vesting over a three-year period. A portion of the Company's restricted stock units are subject to ratable vesting over a four-year period. Compensation expense related to service-based restricted stock units is recognized on a straight-line basis over the vesting period. Restricted stock unit activity for the nine months ended September 30, 2021 is as follows: Number of Weighted- Outstanding on December 31, 2020 707,864 $ 28.35 Granted 254,176 38.84 Vested and converted to common stock (218,950) 30.65 Forfeited (16,080) 30.90 Outstanding on September 30, 2021 727,010 $ 31.27 As of September 30, 2021, there was $10.5 million of pre-tax unrecognized compensation expense related to unvested restricted stock units, which is expected to be recognized over a weighted average of 2.6 years. Performance Stock Units The Company grants performance stock units to certain of its senior executives. The performance stock units are generally subject to a cliff vesting at the end of a three three three Performance stock unit activity for the nine months ended September 30, 2021 is as follows: Number of Weighted- Outstanding on December 31, 2020 234,934 $ 29.80 Granted 106,357 35.99 Vested and converted to common stock (90,284) 30.60 Forfeited (18,150) 30.09 Outstanding on September 30, 2021 232,857 $ 32.29 As of September 30, 2021, there was $5.7 million of pre-tax unrecognized compensation expense related to unvested performance stock units, which is expected to be recognized over a weighted average of 1.9 years. Phantom Stock Units Phantom stock units are grants of phantom stock with respect to shares of the Company's common stock that are settled in cash and are subject to various restrictions, including restrictions on transferability, vesting and forfeiture provisions. Shares of phantom stock that do not vest for any reason will be forfeited by the recipient and will revert to the Company. Phantom stock units were granted to certain employees of the Company and are subject to vesting over a period of four years and certain other conditions, including continued service to the Company. As a result of the cash-settlement feature of the awards, the Company considers the awards to be liability awards, which are measured at fair value at each reporting date and the vested portion of the award is recognized as a liability to the extent that the service condition is deemed probable. The fair value of the phantom stock awards on the balance sheet date was determined using the closing share price of the Company's common stock on that date. The Company recorded phantom stock-based compensation expense of $0.5 million and $0.7 million during the three months ended September 30, 2021 and 2020, respectively. The Company recorded phantom stock-based compensation expense of $6.2 million and less than $0.1 million during the nine months ended September 30, 2021 and 2020, respectively. Phantom stock unit activity for the nine months ended September 30, 2021 is as follows: Number of Outstanding on December 31, 2020 351,634 Granted 63,575 Vested (61,539) Forfeited (4,807) Outstanding on September 30, 2021 348,863 As of September 30, 2021, there was $6.1 million of pre-tax unrecognized compensation expense related to unvested phantom stock units, which is expected to be recognized over a weighted average of 3.1 years.

Restructuring and Related Activ

Restructuring and Related Activities	9 Months Ended
	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities Disclosure	During the three months ended September 30, 2020, the Company implemented a restructuring plan to optimize future growth and profitability. The primary components of the restructuring included a workforce reduction, a reduction of the Company's real estate expenses and professional fees, and the elimination of certain deferred compensation programs. Restructuring charges (reversals) for the three months ended September 30, 2021 by type of charge (reversal) and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 4 $ 9 $ — $ — $ 94 $ 107 Office related (2,891) — — (279) (199) (3,369) Total $ (2,887) $ 9 $ — $ (279) $ (105) $ (3,262) Restructuring charges (reversals) for the nine months ended September 30, 2021 by type of charge (reversal) and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 20 $ (97) $ (124) $ (44) $ 62 $ (183) Office related 3,859 — — 399 (296) 3,962 Other 3 — — — 10 13 Total $ 3,882 $ (97) $ (124) $ 355 $ (224) $ 3,792 Restructuring charges incurred to date, which includes prior period charges, by type of charge and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 16,224 $ 8,257 $ 4,110 $ 2,590 $ 1,415 $ 32,596 Office related 18,101 226 374 2,352 1,819 22,872 Other 34 24 6 71 560 695 Total $ 34,359 $ 8,507 $ 4,490 $ 5,013 $ 3,794 $ 56,163 As part of the Company's reduction in real estate expenses, a lease component related to one of the Company's offices was abandoned. In September 2021, the Company entered into a termination and surrender agreement for this lease component. Under the terms of the agreement, the Company made a one-time payment of $11.7 million to release the Company from all remaining obligations under the lease. At the time of payment, the Company had accrued approximately $17.4 million of lease liabilities related to future payments under the remaining lease term. Upon making the one-time payment, the lease liabilities were relieved, resulting in a gain on termination of approximately $5.7 million, which is recorded in Restructuring charges in the Condensed Consolidated Statements of Comprehensive Income (Loss) for the three and nine months ended September 30, 2021. Changes to the accrual for restructuring charges for the nine months ended September 30, 2021, are as follows: Employee Related Office Related Other Total Outstanding on December 31, 2020 $ 22,312 $ 953 $ — $ 23,265 Restructuring charges (183) 3,962 13 3,792 Cash payments (13,701) (712) (13) (14,426) Non cash write offs 44 (4,147) — (4,103) Other — — — — Exchange rate fluctuations (77) — — (77) Outstanding on September 30, 2021 $ 8,395 $ 56 $ — $ 8,451 Restructuring accruals are recorded within Other current liabilities in the Condensed Consolidated Balance Sheets with the exception of certain employee related accruals. Accruals associated with the elimination of certain deferred compensation programs of $4.9 million and $3.6 million are recorded within current and non-current Accrued salaries and benefits , respectively, as of September 30, 2021. Accruals associated with the elimination of certain deferred compensation programs of $7.2 million and $11.3 million are recorded within current and non-current Accrued salaries and benefits, respectively, as of December 31, 2020.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Tax Disclosure	The Company reported income before taxes of $33.6 million and an income tax provision of $9.1 million for the three months ended September 30, 2021. The Company reported loss before taxes of $36.6 million and an income tax benefit of $10.4 million for the three months ended September 30, 2020. The effective tax rates for the three months ended September 30, 2021 and 2020, were 27.0% and 28.5%, respectively. The effective tax rate for the three months ended September 30, 2021 was impacted by one-time items and the mix of income. The effective tax rate for the three months ended September 30, 2020 was impacted by the tax effect on restructuring expense, the inability to recognize losses, and taxes based on gross receipts. The Company reported income before taxes of $88.1 million and an income tax provision of $28.0 million for the nine months ended September 30, 2021. The Company reported loss before taxes of $43.4 million and an income tax benefit of $0.2 million for the nine months ended September 30, 2020. The effective tax rates for the nine months ended September 30, 2021 and 2020, were 31.8% and 0.5%, respectively. The effective tax rate for the nine months ended September 30, 2021 was impacted by one-time items and the mix of income. The effective tax rate for the nine months ended September 30, 2020 was impacted by the inability to deduct goodwill impairment, the inability to recognize losses, and taxes based on gross receipts, offset by the benefit provided by restructuring expense.

Comprehensive Text Block List

Comprehensive Text Block List	9 Months Ended
	Sep. 30, 2021
Text Block [Abstract]
Comprehensive Income (Loss) Note	The changes in Accumulated other comprehensive income (“AOCI”) by component for the nine months ended September 30, 2021 are as follows: Foreign Pension AOCI Balance at December 31, 2020 $ 6,184 $ (2,767) $ 3,417 Other comprehensive loss before classification, net of tax (1,349) — (1,349) Balance at September 30, 2021 $ 4,835 $ (2,767) $ 2,068

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Segment Reporting Disclosure	In April 2021, the Company acquired BTG, a market-leader in sourcing high-end, on-demand independent talent. As a result of the acquisition, the Company identified a new operating segment, On-Demand Talent. The Company now has five operating segments. The executive search business operates in the Americas, Europe (which includes Africa) and Asia Pacific (which includes the Middle East), and the Heidrick Consulting and On-Demand Talent businesses operate globally. For segment purposes, reimbursements of out-of-pocket expenses classified as revenue and other operating income are reported separately and, therefore, are not included in the results of each segment. The Company believes that analyzing trends in revenue before reimbursements (net revenue), analyzing operating expenses as a percentage of net revenue, and analyzing operating income, more appropriately reflect its core operations. The revenue and operating income (loss) by segment are as follows: Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Revenue Executive Search Americas $ 148,844 $ 79,947 $ 412,740 $ 265,088 Europe 42,676 28,902 125,228 92,108 Asia Pacific 30,126 20,394 87,429 61,654 Total Executive Search 221,646 129,243 625,397 418,850 On-Demand Talent 24,287 — 43,006 — Heidrick Consulting 17,892 14,301 49,059 41,778 Revenue before reimbursements (net revenue) 263,825 143,544 717,462 460,628 Reimbursements 1,490 957 3,819 6,555 Total revenue $ 265,315 $ 144,501 $ 721,281 $ 467,183 Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Operating income (loss) Executive Search Americas (1) $ 38,972 $ (7,934) $ 99,822 $ 40,900 Europe (2) 4,795 (6,856) 13,314 (26,874) Asia Pacific (3) 4,712 (1,726) 13,241 (6,553) Total Executive Search 48,479 (16,516) 126,377 7,473 On-Demand Talent 881 — 1,034 — Heidrick Consulting (4) (2,556) (9,286) (10,897) (21,699) Total segment operating income (loss) 46,804 (25,802) 116,514 (14,226) Global Operations Support (5) (13,462) (12,431) (34,858) (29,841) Total operating income (loss) $ 33,342 $ (38,233) $ 81,656 $ (44,067) (1) Includes restructuring reversal of $2.9 million and restructuring charges of $3.9 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $27.6 million for the three and nine months ended September 30, 2020. (2) Includes restructuring charges of less than $0.1 million and a restructuring reversal of $0.1 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $9.6 million for the three and nine months ended September 30, 2020. Includes goodwill impairment charges of $24.5 million for the nine months ended September 30, 2020. (3) Includes restructuring reversal of $0.1 million for the nine months ended September 30, 2021. Includes restructuring charges of $4.6 million for the three and nine months ended September 30, 2020. Includes goodwill impairment charges of $8.5 million for the nine months ended September 30, 2020. (4) Includes restructuring reversal of $0.3 million and restructuring charges of $0.4 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $4.5 million for the three and nine months ended September 30, 2020.

Guarantees

Guarantees	9 Months Ended
	Sep. 30, 2021
Guarantees and Product Warranties [Abstract]
Guarantees	The Company has utilized letters of credit to support certain obligations, primarily for its office lease agreements. The letters of credit were made to secure the respective agreements and are for the terms of the agreements, which extend through 2033. For each letter of credit issued, the Company would have to use cash to fulfill the obligation if there is a default on a payment. The maximum amount of undiscounted payments the Company would be required to make in the event of default on all outstanding letters of credit is approximately $4.6 million as of September 30, 2021. The Company has not accrued for these arrangements as no event of default exists or is expected to exist.

Commitment and Contingencies

Commitment and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure	Litigation The Company has contingent liabilities from various pending claims and litigation matters arising in the ordinary course of the Company’s business, some of which involve claims for damages that are substantial in amount. Some of these matters are covered by insurance. Based upon information currently available, the Company believes the ultimate resolution of such claims and litigation will not have a material adverse effect on its financial condition, results of operations or liquidity.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	.    Subsequent Event On October 15, 2021, the Company acquired Heidrick & Struggles Finland OY ("H&S Finland"), a Finland-based executive search firm, for initial consideration of $1.6 million with an anticipated future payment in 2023, subject to the achievement of certain agreed upon financial performance targets. The Company previously had an affiliate relationship with H&S Finland, whereby the Company had no financial investment in H&S Finland, but received licensing fees for the use of the Company's name and database.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2021
Business Combinations [Abstract]
Business Combination Disclosure	On April 1, 2021, the Company acquired Business Talent Group, LLC ("BTG"), a market-leader in sourcing high-end, on-demand independent talent. Under the terms of the merger agreement, the Company paid $32.6 million of initial consideration from existing cash for the outstanding equity of BTG. The former owners of BTG are eligible to receive additional cash consideration, which the Company estimates to be between $20.0 million and $30.0 million, based on the achievement of certain revenue and operating income milestones for the period from acquisition through 2022. When estimating the present value of future cash consideration, the Company accrued $23.8 million as of the acquisition date for the earnout liability. The Company recorded $5.8 million for customer relationships, $3.1 million for software, $1.7 million for a trade name and $45.5 million of goodwill. The goodwill is primarily related to the acquired workforce and strategic fit. As of the acquisition date, the Company expects that all of the goodwill will be deductible for tax purposes. The fair value estimate of assets acquired and liabilities assumed, including the earnout liability, identifiable intangible assets and goodwill, is pending completion. The Company expects to finalize its estimates of fair value during the three months ended December 31, 2021. Included in the Company's results of operations for the three and nine months ended September 30, 2021 are $24.3 million and $43.0 million of revenue, respectively, and $0.9 million and $1.0 million of operating income, respectively, from the acquired entity.

Accounting Policies (Tables)

Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of the cash and cash equivalents between the Condensed Consolidated Balance Sheets and the Condensed Consolidated Statements of Cash Flows as of September 30, 2021 and 2020, and December 31, 2020 and 2019: September 30, December 31, 2021 2020 2020 2019 Cash and cash equivalents $ 348,292 $ 170,577 $ 316,473 $ 271,719 Restricted cash included within other non-current assets 34 — 16 — Total cash, cash equivalents and restricted cash $ 348,326 $ 170,577 $ 316,489 $ 271,719
Restrictions on Cash and Cash Equivalents	The following table provides a reconciliation of the cash and cash equivalents between the Condensed Consolidated Balance Sheets and the Condensed Consolidated Statements of Cash Flows as of September 30, 2021 and 2020, and December 31, 2020 and 2019: September 30, December 31, 2021 2020 2020 2019 Cash and cash equivalents $ 348,292 $ 170,577 $ 316,473 $ 271,719 Restricted cash included within other non-current assets 34 — 16 — Total cash, cash equivalents and restricted cash $ 348,326 $ 170,577 $ 316,489 $ 271,719
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic and diluted earnings (loss) per share: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Net income (loss) $ 24,498 $ (26,178) $ 60,095 $ (43,245) Weighted average shares outstanding: Basic 19,569 19,351 19,489 19,281 Effect of dilutive securities: Restricted stock units 524 — 584 — Performance stock units 147 — 186 — Diluted 20,240 19,351 20,259 19,281 Basic earnings (loss) per share $ 1.25 $ (1.35) $ 3.08 $ (2.24) Diluted earnings (loss) per share $ 1.21 $ (1.35) $ 2.97 $ (2.24)

Revenue from Contract with Cu_2

Revenue from Contract with Customer (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Contract with Customer, Contract Asset, Contract Liability, and Receivable	The following table outlines the changes in the contract asset and liability balances from December 31, 2020 to September 30, 2021: September 30, December 31, Change Contract assets Unbilled receivables, net $ 16,584 $ 9,907 $ 6,677 Contract assets 13,886 9,745 4,141 Total contract assets 30,470 19,652 10,818 Contract liabilities Deferred revenue $ 45,284 $ 38,050 $ 7,234

Credit Losses (Tables)

Credit Losses (Tables)	9 Months Ended
	Sep. 30, 2021
Credit Loss [Abstract]
Accounts Receivable, Allowance for Credit Loss	The activity in the allowance for credit losses on the Company's trade receivables is as follows: Balance at December 31, 2020 $ 6,557 Provision for credit losses 4,622 Write-offs (3,523) Foreign currency translation (94) Balance at September 30, 2021 $ 7,562
Debt Securities, Available-for-sale	The fair value and unrealized losses on available for sale debt securities, aggregated by investment category and the length of time the security has been in an unrealized loss position, are as follows: Less Than 12 Months Balance Sheet Classification Balance at September 30, 2021 Fair Value Unrealized Loss Cash and Cash Equivalents Marketable Securities U.S. Treasury securities $ 36,198 $ 1 $ 36,198 $ — Less Than 12 Months Balance Sheet Classification Balance at December 31, 2020 Fair Value Unrealized Loss Cash and Cash Equivalents Marketable Securities U.S. Treasury securities $ 31,997 $ 1 $ 31,997 $ —

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	The components of the Company’s property and equipment are as follows: September 30, December 31, Leasehold improvements $ 35,980 $ 40,320 Office furniture, fixtures and equipment 13,858 14,816 Computer equipment and software 24,714 25,544 Property and equipment, gross 74,552 80,680 Accumulated depreciation (53,613) (57,188) Property and equipment, net $ 20,939 $ 23,492

Leases, Codification Topic 842

Leases, Codification Topic 842 (Tables)	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Lease, Cost	Lease cost components included within General and Administrative Expenses in our Condensed Consolidated Statements of Comprehensive Income (Loss) were as follows: Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Operating lease cost $ 4,682 $ 6,241 $ 14,457 $ 18,688 Variable lease cost 1,480 1,048 3,785 4,832 Total lease cost $ 6,162 $ 7,289 $ 18,242 $ 23,520
Schedule of Cash Flow Information Related to Operating Leases	Supplemental cash flow information related to the Company's operating leases is as follows for the nine months ended September 30: 2021 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 38,387 $ 23,258 Right-of-use assets obtained in exchange for lease obligations: Operating leases $ 4,286 $ 10,581
Lessee Operating Lease Weighted Averages	The weighted average remaining lease term and weighted average discount rate for operating leases as of September 30, is as follows: 2021 2020 Weighted Average Remaining Lease Term Operating leases 6.5 years 4.4 years Weighted Average Discount Rate Operating leases 3.26 % 3.75 %
Lessee, Operating Lease, Liability, Maturity	The future maturities of the Company's operating lease liabilities as of September 30, 2021, for the years ended December 31 is as follows: Operating Lease Maturity 2021 $ 3,976 2022 18,602 2023 16,630 2024 14,592 2025 7,283 Thereafter 30,877 Total lease payments 91,960 Less: Interest (9,632) Present value of lease liabilities $ 82,328

Fair Value Measures and Discl_2

Fair Value Measures and Disclosures (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Unrealized Gain (Loss) on Investments	The Company's cash, cash equivalents, and marketable securities by significant investment category are as follows: Cash and Cash Equivalents Balance at September 30, 2021 Cash $ 165,934 Level 1 (1) : Money market funds 80,161 U.S. Treasury securities 102,197 Total Level 1 182,358 Total $ 348,292 Fair Value Balance Sheet Classification Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash and Cash Equivalents Marketable Securities Balance at December 31, 2020 Cash $ 230,490 $ — Level 1 (1) : Money market funds 53,986 — U.S. Treasury securities $ 51,996 $ 1 $ (1) $ 51,996 31,997 19,999 Total Level 1 51,996 1 (1) 51,996 85,983 19,999 Total $ 51,996 $ 1 $ (1) $ 51,996 $ 316,473 $ 19,999 (1) Level 1 – Quoted prices in active markets for identical assets and liabilities.
Fair Value, Separate Account Investment	The following tables provide a summary of the fair value measurements for each major category of investments, assets designated for retirement and pension plans and associated liabilities measured at fair value: Balance Sheet Classification Fair Value Other Current Assets Assets Designated for Retirement and Pension Plans Investments Other Current Liabilities Retirement and Pension Plans Balance at September 30, 2021 Measured on a recurring basis: Level 1 (1) : U.S. non-qualified deferred compensation plan $ 34,738 $ — $ — $ 34,738 $ — $ — Level 2 (2) : Retirement and pension plan assets 15,031 1,359 13,672 — — — Pension benefit obligation (21,184) — — — (1,359) (19,825) Total Level 2 (6,153) 1,359 13,672 — (1,359) (19,825) Total $ 28,585 $ 1,359 $ 13,672 $ 34,738 $ (1,359) $ (19,825) Balance Sheet Classification Fair Value Other Current Assets Goodwill Assets Designated for Retirement and Pension Plans Investments Other Current Liabilities Retirement and Pension Plans Balance at December 31, 2020 Measured on a recurring basis: Level 1 (1) : U.S. non-qualified deferred compensation plan $ 31,369 $ — $ — $ — $ 31,369 $ — $ — Level 2 (2) : Retirement and pension plan assets 15,859 1,434 — 14,425 — — — Pension benefit obligation (22,351) — — — — (1,434) (20,917) Total Level 2 (6,492) 1,434 — 14,425 — (1,434) (20,917) Measured on a non-recurring basis: Level 3 (3)(4) : Goodwill 91,643 91,643 Total $ 116,520 $ 1,434 $ 91,643 $ 14,425 $ 31,369 $ (1,434) $ (20,917) (1) Level 1 – Quoted prices in active markets for identical assets and liabilities. (2) Level 2 – Quoted prices in active markets for similar assets and liabilities, or other inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument. (3) Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs. (4) In accordance with Subtopic 350-20, goodwill with a carrying value of $33.0 million was written down to its implied fair value of zero during the three months ended June 30, 2020, resulting in the revised total goodwill of $91.6 million and an impairment charge of $33.0 million in earnings.
Investments and Other Noncurrent Assets	The following table provides a reconciliation of the beginning and ending balance of Level 3 liabilities for the nine months ended September 30, 2021: Earnout Contingent Compensation Balance at December 31, 2020 $ — $ (2,390) Acquisition earnout (See Note 8, Acquisitions ) (23,800) — Earnout accretion (363) — Compensation expense — (1,398) Foreign currency translation — 139 Balance at September 30, 2021 $ (24,163) $ (3,649) Earnout accruals and contingent compensation accruals are recorded within Other non-current liabilities and non-current Accrued salaries and benefits, respectively, in the Condensed Consolidated Balance Sheets as of September 30, 2021 and December 31, 2020.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following table provides a reconciliation of the beginning and ending balance of Level 3 liabilities for the nine months ended September 30, 2021: Earnout Contingent Compensation Balance at December 31, 2020 $ — $ (2,390) Acquisition earnout (See Note 8, Acquisitions ) (23,800) — Earnout accretion (363) — Compensation expense — (1,398) Foreign currency translation — 139 Balance at September 30, 2021 $ (24,163) $ (3,649)

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The Company's goodwill by segment is as follows: September 30, December 31, Executive Search Americas $ 91,518 $ 91,643 Total Executive Search 91,518 91,643 On-Demand Talent 45,529 — Total goodwill $ 137,047 $ 91,643
Schedule of Goodwill	Changes in the carrying amount of goodwill by segment for the nine months ended September 30, 2021, are as follows: Executive Search On-Demand Talent Americas Europe Asia Pacific Total Goodwill $ 91,643 $ 24,475 $ 8,495 $ — $ 124,613 Accumulated impairment losses — (24,475) (8,495) — (32,970) Balance at December 31, 2020 91,643 — — — 91,643 BTG acquisition — — — 45,529 45,529 Foreign currency translation (125) — — — (125) Balance at September 30, 2021 $ 91,518 $ — $ — $ 45,529 $ 137,047
Schedule of Finite-Lived Intangible Assets	The Company’s other intangible assets, net by segment, are as follows: September 30, December 31, Executive Search Americas $ 122 $ 225 Europe 544 852 Asia Pacific 37 52 Total Executive Search 703 1,129 On-Demand Talent 9,520 — Total other intangible assets, net $ 10,223 $ 1,129 The carrying amount of amortizable intangible assets and the related accumulated amortization are as follows: Weighted September 30, 2021 December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Client relationships 10.5 $ 22,144 $ (16,000) $ 6,144 $ 16,600 $ (15,587) $ 1,013 Trade name 3.1 2,445 (958) 1,487 280 (164) 116 Software 3.0 3,110 (518) 2,592 — — — Total intangible assets 7.5 $ 27,699 $ (17,476) $ 10,223 $ 16,880 $ (15,751) $ 1,129
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The Company's estimated future amortization expense related to intangible assets as of September 30, 2021, for the years ended December 31 is as follows: 2021 $ 626 2022 2,763 2023 2,885 2024 1,346 2025 801 Thereafter 1,802 Total $ 10,223

Deferred Costs, Capitalized, _2

Deferred Costs, Capitalized, Prepaid, and Other Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Current Assets	The components of other current assets are as follows: September 30, December 31, Contract assets $ 30,470 $ 19,652 Other 3,977 3,627 Total other current assets $ 34,447 $ 23,279

Compensation Related Costs, S_2

Compensation Related Costs, Share Based Payments (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Expensed and Capitalized, Amount	A summary of information with respect to stock-based compensation is as follows: Three Months Ended Nine Months Ended 2021 2020 2021 2020 Salaries and benefits (1) $ 3,321 $ 3,850 $ 14,552 $ 6,645 General and administrative expenses — — 345 460 Income tax benefit related to stock-based compensation included in net income (loss) 886 1,022 3,976 1,886
Share-based Payment Arrangement, Restricted Stock Unit, Activity	Restricted stock unit activity for the nine months ended September 30, 2021 is as follows: Number of Weighted- Outstanding on December 31, 2020 707,864 $ 28.35 Granted 254,176 38.84 Vested and converted to common stock (218,950) 30.65 Forfeited (16,080) 30.90 Outstanding on September 30, 2021 727,010 $ 31.27
Share-based Payment Arrangement, Performance Shares, Outstanding Activity	Number of Weighted- Outstanding on December 31, 2020 234,934 $ 29.80 Granted 106,357 35.99 Vested and converted to common stock (90,284) 30.60 Forfeited (18,150) 30.09 Outstanding on September 30, 2021 232,857 $ 32.29
Share-Based Compensation, Phantom Shares Award Outstanding Activity	Phantom stock unit activity for the nine months ended September 30, 2021 is as follows: Number of Outstanding on December 31, 2020 351,634 Granted 63,575 Vested (61,539) Forfeited (4,807) Outstanding on September 30, 2021 348,863

Restructuring and Related Act_2

Restructuring and Related Activities (Tables)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Restructuring Charges by Type for Current Period	Restructuring charges (reversals) for the three months ended September 30, 2021 by type of charge (reversal) and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 4 $ 9 $ — $ — $ 94 $ 107 Office related (2,891) — — (279) (199) (3,369) Total $ (2,887) $ 9 $ — $ (279) $ (105) $ (3,262)	Restructuring charges (reversals) for the nine months ended September 30, 2021 by type of charge (reversal) and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 20 $ (97) $ (124) $ (44) $ 62 $ (183) Office related 3,859 — — 399 (296) 3,962 Other 3 — — — 10 13 Total $ 3,882 $ (97) $ (124) $ 355 $ (224) $ 3,792
Restructuring Charges by Type Incurred to Date		Restructuring charges incurred to date, which includes prior period charges, by type of charge and reportable segment are as follows: Executive Search Americas Europe Asia Pacific Heidrick Consulting Global Operations Support Total Employee related $ 16,224 $ 8,257 $ 4,110 $ 2,590 $ 1,415 $ 32,596 Office related 18,101 226 374 2,352 1,819 22,872 Other 34 24 6 71 560 695 Total $ 34,359 $ 8,507 $ 4,490 $ 5,013 $ 3,794 $ 56,163
Restructuring and Related Costs		Changes to the accrual for restructuring charges for the nine months ended September 30, 2021, are as follows: Employee Related Office Related Other Total Outstanding on December 31, 2020 $ 22,312 $ 953 $ — $ 23,265 Restructuring charges (183) 3,962 13 3,792 Cash payments (13,701) (712) (13) (14,426) Non cash write offs 44 (4,147) — (4,103) Other — — — — Exchange rate fluctuations (77) — — (77) Outstanding on September 30, 2021 $ 8,395 $ 56 $ — $ 8,451

Comprehensive Text Block List (

Comprehensive Text Block List (Tables)	9 Months Ended
	Sep. 30, 2021
Text Block [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The changes in Accumulated other comprehensive income (“AOCI”) by component for the nine months ended September 30, 2021 are as follows: Foreign Pension AOCI Balance at December 31, 2020 $ 6,184 $ (2,767) $ 3,417 Other comprehensive loss before classification, net of tax (1,349) — (1,349) Balance at September 30, 2021 $ 4,835 $ (2,767) $ 2,068

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The revenue and operating income (loss) by segment are as follows: Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Revenue Executive Search Americas $ 148,844 $ 79,947 $ 412,740 $ 265,088 Europe 42,676 28,902 125,228 92,108 Asia Pacific 30,126 20,394 87,429 61,654 Total Executive Search 221,646 129,243 625,397 418,850 On-Demand Talent 24,287 — 43,006 — Heidrick Consulting 17,892 14,301 49,059 41,778 Revenue before reimbursements (net revenue) 263,825 143,544 717,462 460,628 Reimbursements 1,490 957 3,819 6,555 Total revenue $ 265,315 $ 144,501 $ 721,281 $ 467,183 Three Months Ended September 30, Nine Months Ended 2021 2020 2021 2020 Operating income (loss) Executive Search Americas (1) $ 38,972 $ (7,934) $ 99,822 $ 40,900 Europe (2) 4,795 (6,856) 13,314 (26,874) Asia Pacific (3) 4,712 (1,726) 13,241 (6,553) Total Executive Search 48,479 (16,516) 126,377 7,473 On-Demand Talent 881 — 1,034 — Heidrick Consulting (4) (2,556) (9,286) (10,897) (21,699) Total segment operating income (loss) 46,804 (25,802) 116,514 (14,226) Global Operations Support (5) (13,462) (12,431) (34,858) (29,841) Total operating income (loss) $ 33,342 $ (38,233) $ 81,656 $ (44,067) (1) Includes restructuring reversal of $2.9 million and restructuring charges of $3.9 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $27.6 million for the three and nine months ended September 30, 2020. (2) Includes restructuring charges of less than $0.1 million and a restructuring reversal of $0.1 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $9.6 million for the three and nine months ended September 30, 2020. Includes goodwill impairment charges of $24.5 million for the nine months ended September 30, 2020. (3) Includes restructuring reversal of $0.1 million for the nine months ended September 30, 2021. Includes restructuring charges of $4.6 million for the three and nine months ended September 30, 2020. Includes goodwill impairment charges of $8.5 million for the nine months ended September 30, 2020. (4) Includes restructuring reversal of $0.3 million and restructuring charges of $0.4 million for the three and nine months ended September 30, 2021, respectively. Includes restructuring charges of $4.5 million for the three and nine months ended September 30, 2020.

Accounting Policies (Details)

Accounting Policies (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and Cash Equivalents, at Carrying Value	$ 348,292,000			$ 170,577,000			$ 348,292,000	$ 170,577,000	$ 316,473,000	$ 271,719,000
Cash and Cash Equivalents [Line Items]
Net Income (Loss) Attributable to Parent	$ 24,498,000	$ 20,765,000	$ 14,832,000	$ (26,178,000)	$ (25,733,000)	$ 8,666,000	$ 60,095,000	$ (43,245,000)
Weighted Average Number of Shares Outstanding, Basic	19,569,000			19,351,000			19,489,000	19,281,000
Weighted Average Number of Shares Outstanding, Diluted	20,240,000			19,351,000			20,259,000	19,281,000
Earnings Per Share, Basic	$ 1.25			$ (1.35)			$ 3.08	$ (2.24)
Earnings Per Share, Diluted	$ 1.21			$ (1.35)			$ 2.97	$ (2.24)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 348,326,000			$ 170,577,000			$ 348,326,000	$ 170,577,000	316,489,000	271,719,000
Restricted Stock Units (RSUs)
Cash and Cash Equivalents [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	524,000			0			584,000	0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount				315,000				454,000
Performance Shares
Cash and Cash Equivalents [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	147,000			0			186,000	0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount				63,000				98,000
Other Noncurrent Assets [Member]
Accounting Policies [Abstract]
Restricted Cash	$ 34,000			$ 0			$ 34,000	$ 0	16,000	0
Cash and Cash Equivalents [Line Items]
Restricted Cash	$ 34,000			$ 0			$ 34,000	$ 0	$ 16,000	$ 0

Revenue from Contract with Cu_3

Revenue from Contract with Customer (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Unbilled Contracts Receivable	$ 16,584,000	$ 9,907,000
Contract with Customer, Asset, after Allowance for Credit Loss	13,886,000	9,745,000
Deferred Revenue, Current	45,284,000	38,050,000
Deferred Revenue, Revenue Recognized	33,600,000
Contract with Customer, Performance Obligation Satisfied in Previous Period	26,000,000
Contract with Customer, Asset, before Allowance for Credit Loss, Current	30,470,000	$ 19,652,000
Increase (Decrease) in Unbilled Contracts Receivable	6,677,000
Increase (Decrease) In Contract With Customer, After Allowance For Credit Loss	4,141,000
Increase (Decrease) in Contract with Customer, Asset	10,818,000
Deferred Revenue, Period Increase (Decrease)	$ 7,234,000

Credit Losses (Details)

Credit Losses (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Credit Loss [Abstract]
Allowance for Doubtful Accounts, Premiums and Other Receivables	$ 7,562,000		$ 7,562,000		$ 6,557,000
Accounts Receivable, Credit Loss Expense (Reversal)			4,622,000
Accounts Receivable, Allowance for Credit Loss, Writeoff			(3,523,000)
Debt Securities, Available-for-sale [Line Items]
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation			(94,000)
Allowance for Doubtful Accounts, Premiums and Other Receivables	7,562,000		7,562,000		6,557,000
Accounts Receivable, Credit Loss Expense (Reversal)			4,622,000
Accounts Receivable, Allowance for Credit Loss, Writeoff			3,523,000
Depreciation	1,800,000	$ 2,100,000	5,300,000	$ 6,200,000
Debt Securities, Available-for-sale					51,996,000
US Treasury Securities [Member] | In Loss Position for less than 12 Months
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale	36,198,000		36,198,000		31,997,000
Debt Securities, Unrealized Gain (Loss)			1,000		1,000
Cash and Cash Equivalents | US Treasury Securities [Member] | In Loss Position for less than 12 Months
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale	36,198,000		36,198,000		31,997,000
Investments | US Treasury Securities [Member] | In Loss Position for less than 12 Months
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale	$ 0		$ 0		$ 0

Property, Plant, and Equipmen_2

Property, Plant, and Equipment (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 74,552,000		$ 74,552,000		$ 80,680,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(53,613,000)		(53,613,000)		(57,188,000)
Property, Plant and Equipment, Net	20,939,000		20,939,000		23,492,000
Depreciation	1,800,000	$ 2,100,000	5,300,000	$ 6,200,000
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	35,980,000		35,980,000		40,320,000
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	13,858,000		13,858,000		14,816,000
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 24,714,000		$ 24,714,000		$ 25,544,000

Leases, Codification Topic 84_2

Leases, Codification Topic 842 (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Leases [Abstract]
Operating Lease, Expense	$ 4,682,000	$ 6,241,000	$ 14,457,000	$ 18,688,000
Variable Lease, Cost	1,480,000	1,048,000	3,785,000	4,832,000
Lease, Cost	$ 6,162,000	$ 7,289,000	18,242,000	23,520,000
Operating Lease, Payments			38,387,000	23,258,000
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability			$ 4,286,000	$ 10,581,000
Operating Lease, Weighted Average Remaining Lease Term	6 years 6 months	4 years 4 months 24 days	6 years 6 months	4 years 4 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	3.26%	3.75%	3.26%	3.75%
Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year	$ 3,976,000		$ 3,976,000
Lessee, Operating Lease, Liability, to be Paid, Year One	18,602,000		18,602,000
Lessee, Operating Lease, Liability, to be Paid, Year Two	16,630,000		16,630,000
Lessee, Operating Lease, Liability, to be Paid, Year Three	14,592,000		14,592,000
Lessee, Operating Lease, Liability, to be Paid, Year Four	7,283,000		7,283,000
Lessee, Operating Lease, Liability, to be Paid, After Year Four	30,877,000		30,877,000
Lessee, Operating Lease, Liability, to be Paid	91,960,000		91,960,000
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(9,632,000)		(9,632,000)
Operating Lease, Liability	82,328,000		82,328,000
Lessee, Lease, Description [Line Items]
Restructuring Charges	(3,262,000)	$ 48,115,000	3,792,000	$ 48,115,000	$ 56,163,000
Early Surrender Agreement Payment			11,700,000
Gain on Early Termination Agreement			5,700,000
Lease Liability Associated with Surrendered Office			17,400,000
Office Lease
Lessee, Lease, Description [Line Items]
Restructuring Charges	$ 8,700,000	$ 10,600,000	$ 1,200,000	$ 10,600,000
Minimum [Member] | Office Leases [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	1 year		1 year
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	1 year		1 year
Minimum [Member] | Equipment Lease [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	1 year		1 year
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	1 year		1 year
Maximum [Member] | Office Leases [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	11 years 9 months 18 days		11 years 9 months 18 days
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	11 years 9 months 18 days		11 years 9 months 18 days
Maximum [Member] | Equipment Lease [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	4 years 6 months		4 years 6 months
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	4 years 6 months		4 years 6 months

Fair Value Measures and Discl_3

Fair Value Measures and Disclosures (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 348,292,000	$ 316,473,000	$ 170,577,000	$ 271,719,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax		(1,000)
Debt Securities, Available-for-sale, Amortized Cost		51,996,000
Debt Securities, Available-for-sale		51,996,000
Marketable Securities		19,999,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		1,000
Fair Value, Net Asset (Liability)	28,585,000	116,520,000
Goodwill	137,047,000	91,643,000
Aggregate Cost Basis for Non-Qualified Deferred Compensation Plan	21,200,000	19,500,000
Goodwill, Gross		124,613,000
Goodwill, Impaired, Accumulated Impairment Loss		32,970,000
Europe and Asia Pacific
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill		91,600,000
Goodwill, Gross		33,000,000
Goodwill, Impaired, Accumulated Impairment Loss		33,000,000
Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)	34,738,000	31,369,000
Other Current Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)	1,359,000	1,434,000
Assets Designated for Retirement and Pension Plans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)	13,672,000	14,425,000
Other Current Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)	(1,359,000)	(1,434,000)
Other Pension Plan [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)	(19,825,000)	(20,917,000)
Goodwill [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Net Asset (Liability)		91,643,000
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	182,358,000	85,983,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax		(1,000)
Debt Securities, Available-for-sale, Amortized Cost		51,996,000
Debt Securities, Available-for-sale		51,996,000
Marketable Securities		19,999,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		1,000
Deferred Compensation Plan Assets	34,738,000	31,369,000
Fair Value, Inputs, Level 1 [Member] | Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred Compensation Plan Assets	34,738,000	31,369,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Defined Benefit Plan, Plan Assets, Amount	15,031,000	15,859,000
Defined Benefit Plan, Benefit Obligation	(21,184,000)	(22,351,000)
Fair Value, Net Asset (Liability)	(6,153,000)	(6,492,000)
Fair Value, Inputs, Level 2 [Member] | Other Current Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,359,000	1,434,000
Fair Value, Net Asset (Liability)	1,359,000	1,434,000
Fair Value, Inputs, Level 2 [Member] | Assets Designated for Retirement and Pension Plans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Defined Benefit Plan, Plan Assets, Amount	13,672,000	14,425,000
Fair Value, Net Asset (Liability)	13,672,000	14,425,000
Fair Value, Inputs, Level 2 [Member] | Other Current Liabilities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Defined Benefit Plan, Benefit Obligation	(1,359,000)	(1,434,000)
Fair Value, Net Asset (Liability)	(1,359,000)	(1,434,000)
Fair Value, Inputs, Level 2 [Member] | Other Pension Plan [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Defined Benefit Plan, Benefit Obligation	(19,825,000)	(20,917,000)
Fair Value, Net Asset (Liability)	(19,825,000)	(20,917,000)
Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill		91,643,000
Fair Value, Inputs, Level 3 | Goodwill [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill		91,643,000
Cash [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	165,934,000	230,490,000
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	80,161,000	53,986,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 102,197,000	31,997,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain (Loss), before Tax		(1,000)
Debt Securities, Available-for-sale, Amortized Cost		51,996,000
Debt Securities, Available-for-sale		51,996,000
Marketable Securities		19,999,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		$ 1,000

Fair Value Measures and Discl_4

Fair Value Measures and Disclosures Level 3 Liabilities (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Goodwill, Beginning Balance			$ 91,643,000
Restructuring Charges	$ (3,262,000)	$ 48,115,000	3,792,000	$ 48,115,000	$ 56,163,000
Goodwill, Ending Balance	137,047,000		137,047,000
Business Combination, Contingent Consideration, Liability	(23,800,000)		(23,800,000)
Fair Value, Inputs, Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Goodwill, Beginning Balance			91,643,000
Fair Value, Inputs, Level 3 | Contingent Compensation
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Business Combination, Contingent Consideration, Liability	(23,800,000)		(23,800,000)
Earnout Accretion Fair Value Disclosure			(363,000)
Deferred Compensation Arrangement with Individual, Compensation Expense			(1,398,000)
Acquisition Earnout Accruals	(3,649,000)		(3,649,000)			$ (2,390,000)
Fair Value, Inputs, Level 3 | Acqusition Earnout Accruals
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Acquisition Earnout Accruals	$ (24,163,000)		$ (24,163,000)

Fair Value Measures and Discl_5

Fair Value Measures and Disclosures Level 3 (Details) - Fair Value, Inputs, Level 3	9 Months Ended
	Sep. 30, 2021USD ($)
Acqusition Earnout Accruals
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Acquisition Earnout Accruals	$ (24,163,000)
Contingent Compensation
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Acquisition Earnout Accruals	(2,390,000)
Earnout Accretion Fair Value Disclosure	(363,000)
Fair Value Measurement With Unobservable Inputs, Recurring Basis Liability, Foreign Currency Translation	139,000
Acquisition Earnout Accruals	$ (3,649,000)

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Goodwill [Line Items]
Goodwill	$ 137,047,000		$ 137,047,000		$ 91,643,000
Goodwill, Foreign Currency Translation Gain (Loss)			(125,000)
Goodwill, Gross					124,613,000
Goodwill, Impaired, Accumulated Impairment Loss					(32,970,000)
Goodwill, Acquired During Period			45,529,000
Finite-Lived Intangible Assets, Net	$ 10,223,000		10,223,000		1,129,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years 6 months
Customer Relationships [Member]
Goodwill [Line Items]
Finite-Lived Intangible Assets, Net	$ 6,144,000		6,144,000		1,013,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years 6 months
Europe
Goodwill [Line Items]
Goodwill, Impairment Loss		$ (24,500,000)		$ (24,500,000)
Asia Pacific
Goodwill [Line Items]
Goodwill, Impairment Loss		$ (8,500,000)		$ (8,500,000)
Executive Search Member
Goodwill [Line Items]
Finite-Lived Intangible Assets, Net	$ 703,000		703,000		1,129,000
Executive Search Member | Americas
Goodwill [Line Items]
Goodwill	91,518,000		91,518,000		91,643,000
Goodwill, Foreign Currency Translation Gain (Loss)			(125,000)
Goodwill, Gross					91,643,000
Goodwill, Impaired, Accumulated Impairment Loss					0
Finite-Lived Intangible Assets, Net	122,000		122,000		225,000
Executive Search Member | Europe
Goodwill [Line Items]
Goodwill	0		0		0
Goodwill, Foreign Currency Translation Gain (Loss)			0
Goodwill, Gross					24,475,000
Goodwill, Impaired, Accumulated Impairment Loss					(24,475,000)
Finite-Lived Intangible Assets, Net	544,000		544,000		852,000
Executive Search Member | Asia Pacific
Goodwill [Line Items]
Goodwill	0		0		0
Goodwill, Foreign Currency Translation Gain (Loss)			0
Goodwill, Gross					8,495,000
Goodwill, Impaired, Accumulated Impairment Loss					(8,495,000)
Finite-Lived Intangible Assets, Net	37,000		37,000		$ 52,000
On-Demand Talent
Goodwill [Line Items]
Goodwill	45,529,000		45,529,000
Finite-Lived Intangible Assets, Net	$ 9,520,000		$ 9,520,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years 4 months 24 days
On-Demand Talent | Customer Relationships [Member]
Goodwill [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	11 years

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Other Intangible Assets, net (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year	$ 626,000		$ 626,000
Finite-Lived Intangible Asset, Expected Amortization, Year Two	2,763,000		2,763,000
Finite-Lived Intangible Asset, Expected Amortization, Year Three	2,885,000		2,885,000
Finite-Lived Intangible Asset, Expected Amortization, Year Four	1,346,000		1,346,000
Finite-Lived Intangible Asset, Expected Amortization, Year Five	801,000		801,000
Finite-Lived Intangible Asset, Expected Amortization, after Year Five	1,802,000		1,802,000
Finite-Lived Intangible Assets, Net	$ 10,223,000		10,223,000		$ 1,129,000
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years 6 months
Finite-Lived Intangible Assets, Gross	$ 27,699,000		27,699,000		16,880,000
Finite-Lived Intangible Assets, Accumulated Amortization	(17,476,000)		(17,476,000)		(15,751,000)
Finite-Lived Intangible Assets, Net	10,223,000		10,223,000		1,129,000
Amortization of Intangible Assets	800,000	$ 200,000	1,800,000	$ 600,000
Capitalized Computer Software, Gross	3,100,000		3,100,000
Finite-Lived Trade Names, Gross	1,700,000		1,700,000
Executive Search Member
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	703,000		703,000		1,129,000
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	703,000		703,000		1,129,000
Executive Search Member | Americas
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	122,000		122,000		225,000
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	122,000		122,000		225,000
Executive Search Member | Asia Pacific
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	37,000		37,000		52,000
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	37,000		37,000		52,000
Executive Search Member | Europe
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	544,000		544,000		852,000
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	544,000		544,000		852,000
On-Demand Talent
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	$ 9,520,000		9,520,000
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years 4 months 24 days
Finite-Lived Intangible Assets, Net	$ 9,520,000		9,520,000
Customer Relationships [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	$ 6,144,000		6,144,000		1,013,000
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years 6 months
Finite-Lived Intangible Assets, Gross	$ 22,144,000		22,144,000		16,600,000
Finite-Lived Intangible Assets, Accumulated Amortization	(16,000,000)		(16,000,000)		(15,587,000)
Finite-Lived Intangible Assets, Net	$ 6,144,000		6,144,000		1,013,000
Customer Relationships [Member] | On-Demand Talent
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	11 years
Trade Names [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	$ 1,487,000		1,487,000		116,000
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years 1 month 6 days
Finite-Lived Intangible Assets, Gross	$ 2,445,000		2,445,000		280,000
Finite-Lived Intangible Assets, Accumulated Amortization	(958,000)		(958,000)		(164,000)
Finite-Lived Intangible Assets, Net	$ 1,487,000		1,487,000		$ 116,000
Trade Names [Member] | On-Demand Talent
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years
Software and Software Development Costs
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Net	$ 2,592,000		2,592,000
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years
Finite-Lived Intangible Assets, Gross	$ 3,110,000		3,110,000
Finite-Lived Intangible Assets, Accumulated Amortization	(518,000)		(518,000)
Finite-Lived Intangible Assets, Net	$ 2,592,000		$ 2,592,000
Software and Software Development Costs | On-Demand Talent
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years

Deferred Costs, Capitalized, _3

Deferred Costs, Capitalized, Prepaid, and Other Assets (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Unbilled Receivables, Current	$ 30,470,000	$ 19,652,000
Other Assets, Miscellaneous, Current	3,977,000	3,627,000
Other Assets, Current	$ 34,447,000	$ 23,279,000

Debt (Details)

Debt (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 13, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Line of Credit Facility, Maximum Borrowing Capacity		$ 175,000,000		$ 200,000,000
Proceeds from Lines of Credit	$ 100,000,000	0	$ 100,000,000
Long-term Line of Credit		0			$ 0
Sub Limit for Letters of Credit		25,000,000
Line of Credit Facility Expansion Borrowing Capacity		75,000,000
Swingline Loan Sub Limit		10,000,000
Repayments of Lines of Credit	$ 100,000,000	$ 0	$ 100,000,000

Compensation Related Costs, S_3

Compensation Related Costs, Share Based Payments (Details) - USD ($)	May 28, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period				3,369,759
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		742,624		742,624
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares				722,865
Share-based Payment Arrangement, Expense, Tax Benefit		$ 886,000	$ 1,022,000	$ 3,976,000	$ 1,886,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	500,000
Labor and Related Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expensed and Capitalized, Amount		3,321,000	3,850,000	14,552,000	6,645,000
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expensed and Capitalized, Amount		0	0	345,000	460,000
Restricted Stock Units (RSUs)
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		10,500,000		$ 10,500,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 7 months 6 days
Share-based Payment Arrangement, Expense		500,000	700,000	$ 6,200,000	0.1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense		500,000	$ 700,000	6,200,000	$ 0.1
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 10,500,000		$ 10,500,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		727,010		727,010		707,864
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value		$ 31.27		$ 31.27		$ 28.35
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				254,176
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period				(218,950)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period				(16,080)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 38.84
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value				30.65
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value				$ 30.90
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		727,010		727,010		707,864
Performance Shares
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 5,700,000		$ 5,700,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		5,700,000		$ 5,700,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			232,857		232,857	234,934
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value			$ 32.29		$ 32.29	$ 29.80
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				106,357
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period				(90,284)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period				(18,150)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 35.99
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value				30.60
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value				$ 30.09
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			232,857		232,857	234,934
Performance Shares | Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				3 years
Phantom Share Units (PSUs) [Member]
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		6,100,000		$ 6,100,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				3 years 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 6,100,000		$ 6,100,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				3 years 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			348,863		348,863	351,634
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				63,575
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period				(61,539)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period				(4,807)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			348,863		348,863	351,634

Restructuring and Related Act_3

Restructuring and Related Activities - Restructuring Charges by Segment and Type (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ (3,262,000)	$ 48,115,000	$ 3,792,000	$ 48,115,000	$ 56,163,000
Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(105,000)	1,900,000	(224,000)	1,900,000	3,794,000
Heidrick Consulting
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(300,000)	4,500,000	400,000	4,500,000
Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(279,000)		355,000		5,013,000
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(107,000)		183,000		32,596,000
Employee Severance | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	94,000		62,000		1,415,000
Employee Severance | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(44,000)		2,590,000
Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3,369,000		(3,962,000)		22,872,000
Facility Closing | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(199,000)		(296,000)		1,819,000
Facility Closing | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(279,000)		399,000		2,352,000
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			(13,000)		695,000
Other Restructuring | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			10,000		560,000
Other Restructuring | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0		71,000
Americas
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,900,000)		3,900,000	27,600,000
Americas | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,887,000)		3,882,000		34,359,000
Americas | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	4,000		20,000		16,224,000
Americas | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,891,000)		3,859,000		18,101,000
Americas | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			3,000		34,000
Europe
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(0.1)	(9,600,000)	100,000	(9,600,000)
Europe | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	9,000		(97,000)		8,507,000
Europe | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	9,000		(97,000)		8,257,000
Europe | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		0		226,000
Europe | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0		24,000
Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ (4,600,000)	100,000	$ (4,600,000)
Asia Pacific | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(124,000)		4,490,000
Asia Pacific | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(124,000)		4,110,000
Asia Pacific | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 0		0		374,000
Asia Pacific | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			$ 0		$ 6,000

Restructuring and Related Act_4

Restructuring and Related Activities - Restructuring Charges by Segment and Type Incurred to Date(Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ (3,262,000)	$ 48,115,000	$ 3,792,000	$ 48,115,000	$ 56,163,000
Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(105,000)	1,900,000	(224,000)	1,900,000	3,794,000
Heidrick Consulting
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(300,000)	4,500,000	400,000	4,500,000
Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(279,000)		355,000		5,013,000
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(107,000)		183,000		32,596,000
Employee Severance | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	94,000		62,000		1,415,000
Employee Severance | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(44,000)		2,590,000
Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3,369,000		(3,962,000)		22,872,000
Facility Closing | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(199,000)		(296,000)		1,819,000
Facility Closing | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(279,000)		399,000		2,352,000
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			(13,000)		695,000
Other Restructuring | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			10,000		560,000
Other Restructuring | Heidrick Consulting | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0		71,000
Americas
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,900,000)		3,900,000	27,600,000
Americas | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,887,000)		3,882,000		34,359,000
Americas | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	4,000		20,000		16,224,000
Americas | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,891,000)		3,859,000		18,101,000
Americas | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			3,000		34,000
Europe
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(0.1)	(9,600,000)	100,000	(9,600,000)
Europe | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	9,000		(97,000)		8,507,000
Europe | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	9,000		(97,000)		8,257,000
Europe | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		0		226,000
Europe | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			0		24,000
Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ (4,600,000)	100,000	$ (4,600,000)
Asia Pacific | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(124,000)		4,490,000
Asia Pacific | Employee Severance | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0		(124,000)		4,110,000
Asia Pacific | Facility Closing | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 0		0		374,000
Asia Pacific | Other Restructuring | Executive Search Member | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring Charges			$ 0		$ 6,000

Restructuring and Related Act_5

Restructuring and Related Activities (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 8,451,000		$ 8,451,000			$ 23,265,000
Restructuring Charges	(3,262,000)	$ 48,115,000	3,792,000	$ 48,115,000	$ 56,163,000
Payments for Restructuring			(14,426,000)
Restructuring Reserve, Settled without Cash			(4,103,000)
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			(77,000)
Other Restructuring Costs			0
Early Surrender Agreement Payment			11,700,000
Lease Liability Associated with Surrendered Office			17,400,000
Gain on Early Termination Agreement			5,700,000
Americas
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(2,900,000)		3,900,000	27,600,000
Europe
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(0.1)	(9,600,000)	100,000	(9,600,000)
Asia Pacific
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		(4,600,000)	100,000	(4,600,000)
Employee-related Liabilities, Current
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	4,900,000		4,900,000			7,200,000
Accrued Salaries and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	3,600,000		3,600,000			11,300,000
Heidrick Consulting
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	(300,000)	$ 4,500,000	400,000	$ 4,500,000
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	8,395,000		8,395,000			22,312,000
Restructuring Charges	(107,000)		183,000		32,596,000
Payments for Restructuring			(13,701,000)
Restructuring Reserve, Settled without Cash			44,000
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			(77,000)
Other Restructuring Costs			0
Facility Closing
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	56,000		56,000			953,000
Restructuring Charges	3,369,000		(3,962,000)		22,872,000
Payments for Restructuring			(712,000)
Restructuring Reserve, Settled without Cash			(4,147,000)
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Other Restructuring Costs			0
Other Restructuring
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0		0			$ 0
Restructuring Charges			(13,000)		$ 695,000
Payments for Restructuring			(13,000)
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve, Foreign Currency Translation Gain (Loss)			0
Other Restructuring Costs			$ 0

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	27.00%	28.50%	31.80%	0.50%
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ 33,577	$ (36,594)	$ 88,123	$ (43,447)
Income Tax Expense (Benefit)	$ 9,079	$ (10,416)	$ 28,028	$ (202)

Comprehensive Text Block List_2

Comprehensive Text Block List (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ 2,068,000		$ 2,068,000				$ 3,417,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	323,256,000	$ 261,066,000	323,256,000	$ 261,066,000	$ 299,553,000	$ 278,570,000	267,602,000	$ 286,203,000	$ 311,765,000	$ 309,115,000
Restructuring Charges	3,262,000	(48,115,000)	(3,792,000)	(48,115,000)	(56,163,000)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	4,835,000		4,835,000				6,184,000
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent			(1,349,000)
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(2,767,000)		(2,767,000)				(2,767,000)
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent			0
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 2,068,000	$ 2,429,000	2,068,000	$ 2,429,000	$ 2,729,000	$ 2,724,000	$ 3,417,000	$ 1,579,000	$ 78,000	$ 3,824,000
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent			$ (1,349,000)

Segment Reporting (Details)

Segment Reporting (Details) - USD ($)	3 Months Ended		9 Months Ended		21 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 263,825,000	$ 143,544,000	$ 717,462,000	$ 460,628,000
Revenues	265,315,000	144,501,000	721,281,000	467,183,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	33,342,000	(38,233,000)	81,656,000	(44,067,000)
Restructuring Charges	3,262,000	(48,115,000)	(3,792,000)	(48,115,000)	$ (56,163,000)
Reimbursements
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	1,490,000	957,000	3,819,000	6,555,000
Americas
Operating Income (Loss) [Abstract]
Restructuring Charges	2,900,000		(3,900,000)	(27,600,000)
Europe
Operating Income (Loss) [Abstract]
Goodwill, Impairment Loss		24,500,000		24,500,000
Restructuring Charges	0.1	9,600,000	(100,000)	9,600,000
Asia Pacific
Operating Income (Loss) [Abstract]
Goodwill, Impairment Loss		8,500,000		8,500,000
Restructuring Charges		4,600,000	(100,000)	4,600,000
Heidrick Consulting
Operating Income (Loss) [Abstract]
Restructuring Charges	300,000	(4,500,000)	(400,000)	(4,500,000)
On-Demand Talent
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	24.3		43
Operating Income (Loss) [Abstract]
Operating Income (Loss)	0.9		1
Operating Segments
Operating Income (Loss) [Abstract]
Operating Income (Loss)	46,804,000	(25,802,000)	116,514,000	(14,226,000)
Operating Segments | Executive Search Member
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	221,646,000	129,243,000	625,397,000	418,850,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	48,479,000	(16,516,000)	126,377,000	7,473,000
Operating Segments | Executive Search Member | Americas
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	148,844,000	79,947,000	412,740,000	265,088,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	38,972,000	(7,934,000)	99,822,000	40,900,000
Restructuring Charges	2,887,000		(3,882,000)		(34,359,000)
Operating Segments | Executive Search Member | Europe
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	42,676,000	28,902,000	125,228,000	92,108,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	4,795,000	(6,856,000)	13,314,000	(26,874,000)
Restructuring Charges	(9,000)		97,000		(8,507,000)
Operating Segments | Executive Search Member | Asia Pacific
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	30,126,000	20,394,000	87,429,000	61,654,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	4,712,000	(1,726,000)	13,241,000	(6,553,000)
Restructuring Charges	0		124,000		(4,490,000)
Operating Segments | Heidrick Consulting
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	17,892,000	14,301,000	49,059,000	41,778,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	(2,556,000)	(9,286,000)	(10,897,000)	(21,699,000)
Restructuring Charges	279,000		(355,000)		(5,013,000)
Operating Segments | On-Demand Talent
Revenues [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	24,287,000		43,006,000
Operating Income (Loss) [Abstract]
Operating Income (Loss)	881,000		1,034,000
Corporate, Non-Segment
Operating Income (Loss) [Abstract]
Operating Income (Loss)	(13,462,000)	(12,431,000)	(34,858,000)	(29,841,000)
Restructuring Charges	$ 105,000	$ (1,900,000)	$ 224,000	$ (1,900,000)	$ (3,794,000)

Guarantees (Details)

Guarantees (Details)	Sep. 30, 2021USD ($)
Guarantees and Product Warranties [Abstract]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 4,600,000

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Oct. 15, 2021	Jul. 13, 2021	Apr. 01, 2021
Subsequent Event [Line Items]
Payments to Acquire Businesses, Gross	$ 31,969,000	$ 0
Line of Credit Facility, Maximum Borrowing Capacity	175,000,000			$ 200,000,000
Sub Limit for Letters of Credit	25,000,000
Swingline Loan Sub Limit	10,000,000
Line of Credit Facility Expansion Borrowing Capacity	$ 75,000,000
Business Acquisition, Transaction Costs			$ 1,600,000		$ 32,600,000

Business Combinations (Details)

Business Combinations (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Oct. 15, 2021	Apr. 01, 2021
Business Combinations [Abstract]
Business Combination, Contingent Consideration, Liability	$ 23,800,000		$ 23,800,000
Finite-Lived Customer Relationships, Gross	5,800,000		5,800,000
Capitalized Computer Software, Gross	3,100,000		3,100,000
Finite-Lived Trade Names, Gross	1,700,000		1,700,000
Goodwill, Acquired During Period			45,529,000
Revenue from Contract with Customer, Excluding Assessed Tax	263,825,000	$ 143,544,000	717,462,000	$ 460,628,000
Operating Income (Loss)	33,342,000	(38,233,000)	81,656,000	(44,067,000)
Business Acquisition, Transaction Costs					$ 1,600,000	$ 32,600,000
Business Acquisition [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	263,825,000	143,544,000	717,462,000	460,628,000
Operating Income (Loss)	33,342,000	$ (38,233,000)	81,656,000	$ (44,067,000)
On-Demand Talent
Business Combinations [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	24.3		43
Operating Income (Loss)	0.9		1
Business Acquisition [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	24.3		43
Operating Income (Loss)	0.9		1
On-Demand Talent
Business Combinations [Abstract]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	20,000,000		20,000,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	30,000,000		30,000,000
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	20,000,000		20,000,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 30,000,000		$ 30,000,000