CBIZ (CBZ) 10-Q 30 Apr 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 23, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	1-32961
Entity Registrant Name	CBIZ, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-2769024
Entity Address, Address Line One	6050 Oak Tree Boulevard
Entity Address, Address Line Two	South
Entity Address, Address Line Three	Suite 500
Entity Address, City or Town	Cleveland
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	44131
City Area Code	216
Local Phone Number	447-9000
Title of 12(b) Security	Common Stock, $0.01 Par Value
Trading Symbol	CBZ
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		53,176,480
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000944148
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 6,778	$ 4,652
Restricted cash	27,618	23,951
Accounts receivable, net	270,610	216,175
Other current assets	25,695	24,213
Current assets before funds held for clients	330,701	268,991
Funds held for clients	140,774	167,440
Total current assets	471,475	436,431
Non-current assets:
Property and equipment, net	39,910	41,346
Goodwill and other intangible assets, net	756,684	756,750
Assets of deferred compensation plan	133,478	127,332
Operating lease right-of-use assets, net	146,786	147,843
Other non-current assets	3,510	4,052
Total non-current assets	1,080,368	1,077,323
Total assets	1,551,843	1,513,754
Current liabilities:
Accounts payable	60,216	64,119
Income taxes payable	15,028	2,788
Accrued personnel costs	50,223	79,978
Contingent purchase price liabilities	22,767	20,288
Operating lease liabilities	30,638	30,483
Other current liabilities	14,312	13,629
Current liabilities before client fund obligations	193,184	211,285
Client fund obligations	140,490	166,989
Total current liabilities	333,674	378,274
Non-current liabilities:
Bank debt	162,000	108,000
Debt issuance costs	(718)	(808)
Total long-term debt	161,282	107,192
Income taxes payable	1,339	1,775
Deferred income taxes, net	12,371	8,752
Deferred compensation plan obligations	133,478	127,332
Contingent purchase price liabilities	31,463	34,103
Operating lease liabilities	140,150	142,020
Other non-current liabilities	10,303	11,686
Total non-current liabilities	490,386	432,860
Total liabilities	824,060	811,134
STOCKHOLDERS' EQUITY
Common stock	1,346	1,341
Additional paid in capital	749,207	740,970
Retained earnings	608,084	557,875
Treasury stock	(629,439)	(595,297)
Accumulated other comprehensive loss	(1,415)	(2,269)
Total stockholders’ equity	727,783	702,620
Total liabilities and stockholders’ equity	$ 1,551,843	$ 1,513,754

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Revenue	$ 300,730	$ 277,455
Operating expenses	223,971	199,827
Gross margin	76,759	77,628
Corporate general and administrative expenses	14,483	10,489
Operating income	62,276	67,139
Other income (expense):
Interest expense	(877)	(1,119)
Gain on sale of operations, net	0	95
Other income (expense), net	4,789	(15,800)
Total other income (expense), net	3,912	(16,824)
Income from continuing operations before income tax    expense	66,188	50,315
Income tax expense	15,972	13,453
Income from continuing operations	50,216	36,862
Loss from discontinued operations, net of tax	(7)	(14)
Net income	$ 50,209	$ 36,848
Basic:
Continuing operations (in dollars per share)	$ 0.94	$ 0.68
Discontinued operations (in dollars per share)	0	0
Net income (in dollars per share)	0.94	0.68
Diluted:
Continuing operations (in dollars per share)	0.92	0.66
Discontinued operations (in dollars per share)	0	0
Net income (in dollars per share)	$ 0.92	$ 0.66
Basic weighted average shares outstanding (in shares)	53,366	54,571
Diluted weighted average shares outstanding (in shares)	54,436	55,945
Comprehensive income:
Net income	$ 50,209	$ 36,848
Other comprehensive income (loss), net of tax	854	(1,252)
Comprehensive income	$ 51,063	$ 35,596

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2019		133,056	77,637
Beginning balance at Dec. 31, 2019	$ 659,238	$ 1,331	$ (535,693)	$ 714,704	$ 479,576	$ (680)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	36,848				36,848
Other comprehensive income (loss)	(1,252)					(1,252)
Share repurchases (in shares)			1,174
Share repurchases	(29,487)		$ (29,487)
Stock options exercised (in shares)		116
Stock options exercised	1,013	$ 1		1,012
Stock-based compensation	2,023			2,023
Business acquisitions (in shares)		69
Business acquisitions	1,877			1,877
Ending balance (in shares) at Mar. 31, 2020		133,241	78,811
Ending balance at Mar. 31, 2020	670,260	$ 1,332	$ (565,180)	719,616	516,424	(1,932)
Beginning balance (in shares) at Dec. 31, 2020		134,144	80,045
Beginning balance at Dec. 31, 2020	702,620	$ 1,341	$ (595,297)	740,970	557,875	(2,269)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	50,209				50,209
Other comprehensive income (loss)	854					854
Share repurchases (in shares)			1,164
Share repurchases	(34,142)		$ (34,142)
Restricted stock units and awards (in shares)		46
Restricted stock units and awards	$ 0	$ 1		(1)
Stock options exercised (in shares)	397	397
Stock options exercised	$ 4,408	$ 4		4,404
Stock-based compensation	2,855			2,855
Business acquisitions (in shares)		38
Business acquisitions	979			979
Ending balance (in shares) at Mar. 31, 2021		134,625	81,209
Ending balance at Mar. 31, 2021	$ 727,783	$ 1,346	$ (629,439)	$ 749,207	$ 608,084	$ (1,415)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income	$ 50,209	$ 36,848
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization expense	6,252	5,704
Bad debt expense, net of recoveries	58	2,289
Adjustment to contingent earnout liability	660	(684)
Stock-based compensation expense	2,855	2,023
Excess tax benefits from share based payment arrangements	(2,179)	(501)
Deferred income taxes	3,348	170
Other, net	96	20
Changes in assets and liabilities, net of acquisitions and divestitures:
Accounts receivable, net	(54,651)	(42,566)
Other assets	(997)	(1,237)
Accounts payable	(4,873)	(6,336)
Income taxes payable	13,984	13,665
Accrued personnel costs	(29,755)	(30,201)
Other liabilities	172	2,175
Operating cash flows used in continuing operations	(14,821)	(18,631)
Operating cash flows used in discontinued operations	(6)	(16)
Net cash used in operating activities	(14,827)	(18,647)
Cash flows from investing activities:
Business acquisitions and purchases of client lists, net of cash acquired	(2,012)	(7,848)
Purchases of client fund investments	0	(3,447)
Proceeds from the sales and maturities of client fund investments	3,090	17,118
Increase in funds held for clients	83	822
Additions to property and equipment	(1,146)	(2,641)
Other	214	351
Net cash provided by investing activities	229	4,355
Cash flows from financing activities:
Proceeds from bank debt	235,700	379,754
Payment of bank debt	(181,700)	(102,254)
Payment for acquisition of treasury stock	(33,142)	(29,487)
Decrease in client funds obligations	(26,499)	(38,517)
Proceeds from exercise of stock options	4,408	1,013
Payment of contingent consideration for acquisitions	(1,670)	(2,624)
Other, net	(57)	(113)
Net cash (used in) provided by financing activities	(2,960)	207,772
Net (decrease) increase in cash, cash equivalents and restricted cash	(17,558)	193,480
Cash, cash equivalents and restricted cash at beginning of year	170,335	146,505
Cash, cash equivalents and restricted cash at end of period	152,777	339,985
Reconciliation of cash, cash equivalents and restricted cash to the    Consolidated Balance Sheets:
Total cash, cash equivalents and restricted cash	$ 152,777	$ 339,985

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Selected Terms Used in Notes to the Condensed Consolidated Financial Statements ASA – Administrative Service Agreement ASC – Accounting Standards Codification ASU – Accounting Standards Update CECL– Current expected credit losses CPA firm – Certified Public Accounting firm FASB – The Financial Accounting Standards Board GAAP – United States Generally Accepted Accounting Principles LIBOR – London Interbank Offered Rate SEC – United States Securities and Exchange Commission Description of Business: CBIZ, Inc. is a diversified services company which, acting through its subsidiaries, has been providing professional business services since 1996, primarily to small and medium-sized businesses, as well as individuals, governmental entities, and not-for-profit enterprises throughout the United States and parts of Canada. CBIZ, Inc. manages and reports its operations along three practice groups: Financial Services, Benefits and Insurance Services and National Practices. A further description of products and services offered by each of the practice groups is provided in Note 12. Segment Disclosures, to the accompanying condensed consolidated financial statements. Basis of Consolidation: The accompanying unaudited condensed consolidated financial statements include the operations of CBIZ, Inc. and all of its wholly-owned subsidiaries (“CBIZ”, the “Company”, “we”, “us”, or “our”), after elimination of all intercompany balances and transactions. These condensed consolidated financial statements do not reflect the operations or accounts of variable interest entities as the impact is not material to the financial condition, results of operations or cash flows of CBIZ. Unaudited Interim Financial Statements: The condensed consolidated financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this quarterly report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020. In the opinion of CBIZ management, the accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the financial condition, results of operations, and cash flows for the interim periods presented, but are not necessarily indicative of the results of operations to be anticipated for the full year ending December 31, 2021. Use of Estimates: The preparation of condensed consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Changes in circumstances could cause actual results to differ materially from these estimates. Changes in Accounting Policies: We have consistently applied the accounting policies for the periods presented as described in Note 1, Basis of Presentation and Significant Accounting Policies, to the consolidated financial statements contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020.

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2021
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTSThe FASB ASC is the sole source of authoritative GAAP other than the SEC issued rules and regulations that apply only to SEC registrants. The FASB issues an accounting standard to communicate changes to the FASB codification. We assess and review the impact of all accounting standards. Any accounting standards not listed below were reviewed and determined to be either not applicable or are not expected to have a material impact on the consolidated financial statements of the Company. Accounting Standards Issued But Not Yet Adopted Reference Rate Reform : In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting , which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this ASU are effective for all entities through December 31, 2022. We are currently evaluating the effect of this new standard on our consolidated financial statements and have not adopted any of the transition relief available under the new guidance as of March 31, 2021. Subsequently, in January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848): Scope

Accounts Receivable, Net

Accounts Receivable, Net	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
Accounts Receivable, Net	ACCOUNTS RECEIVABLE, NET Accounts receivable, less allowance for doubtful accounts, reflects the net realizable value of receivables and approximates fair value. Unbilled revenues are recorded at estimated net realizable value. Assessing the collectability of the receivables (billed and unbilled) requires management judgment based on a combination of factors, including but not limited to, an evaluation of our historical incurred loss experience, credit-worthiness of our clients, age of the trade receivable balance, current economic conditions that may affect a client’s ability to pay, and reasonable and supportable forecasts. Receivables are charged-off against the allowance when the balance is deemed uncollectible. Accounts receivable, net, at March 31, 2021 and December 31, 2020 were as follows (in thousands): March 31, December 31, Trade accounts receivable $ 177,104 $ 167,575 Unbilled revenue, at net realizable value 106,662 63,494 Total accounts receivable 283,766 231,069 Allowance for doubtful accounts (13,156) (14,894) Accounts receivable, net $ 270,610 $ 216,175 Changes to the allowance for doubtful accounts for the three months ended March 31, 2021 and twelve months ended December 31, 2020 are as follows (in thousands): March 31, December 31, 2020 Balance at beginning of period $ (14,894) $ (14,379) Provision (390) (9,323) Charge-offs, net of recoveries 2,128 8,808 Allowance for doubtful accounts $ (13,156) $ (14,894)

Debt and Financing Arrangements

Debt and Financing Arrangements	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Debt and Financing Arrangements	DEBT AND FINANCING ARRANGEMENTS 2018 Credit Facility - Our primary financing arrangement is the $400 million unsecured credit facility (the “2018 credit facility” or the “credit facility”), which provides us with the capital necessary to meet our working capital needs as well as the flexibility to continue with our strategic initiatives, including business acquisitions and share repurchases. The 2018 credit facility matures in 2023. The balance outstanding under the 2018 credit facility was $162.0 million and $108.0 million at March 31, 2021 and December 31, 2020, respectively. Effective interest rates, including the impact of interest rate swaps associated with the 2018 credit facility, were as follows: Three Months Ended 2021 2020 Weighted average rates 2.10% 2.50% Range of effective rates 1.08% - 3.64% 1.61% - 4.75% We had approximately $228.7 million of available funds under the credit facility at March 31, 2021, net of outstanding letters of credit of $3.0 million. As of March 31, 2021, we were in compliance with our debt covenants. Other Line of Credit - We have an unsecured $20.0 million line of credit by and among CBIZ Benefits and Insurance, Inc. and Huntington National Bank. We utilize this line to support our short-term funding requirements of payroll client fund obligations due to the investment of client funds, rather than liquidating client funds that have already been invested in available-for-sale securities. The line of credit, which was renewed on August 6, 2020 and will terminate on August 5, 2021, did not have a balance outstanding at March 31, 2021. Refer to our Annual Report on Form 10-K for the year ended December 31, 2020 for additional details of our debt and financing arrangements. Interest Expense - Interest expense, including amortization of deferred financing costs, commitment fees, line of credit fees, and other applicable bank charges, was as follows (in thousands): Three Months Ended March 31, 2021 2020 2018 credit facility $ 871 $ 1,101 Other line of credit — 1 Other 6 17 Total $ 877 $ 1,119

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Letters of Credit and Guarantees - We provide letters of credit to landlords (lessors) of our leased premises in lieu of cash security deposits, which totaled $3.0 million and $1.7 million at March 31, 2021 and December 31, 2020, respectively. In addition, we provide license bonds to various state agencies to meet certain licensing requirements. The amount of license bonds outstanding was $2.3 million and $2.2 million at March 31, 2021 and December 31, 2020, respectively. Legal Proceedings - In 2010, CBIZ, Inc. and its subsidiary, CBIZ MHM, LLC (fka CBIZ Accounting, Tax & Advisory Services, LLC) (the “CBIZ Parties”), were named as defendants in lawsuits filed in the U.S. District Court for the District of Arizona and the Superior Court for Maricopa County, Arizona. The federal court case is captioned Robert Facciola, et al v. Greenberg Traurig LLP, et al, and the state court cases are captioned Victims Recovery, LLC v. Greenberg Traurig LLP, et al, Roger Ashkenazi, et al v. Greenberg Traurig LLP, et al, Mary Marsh, et al v. Greenberg Traurig LLP, et al; and ML Liquidating Trust v. Mayer Hoffman McCann, P.C. (“Mayer Hoffman”), et al. Prior to these suits CBIZ MHM, LLC was named as a defendant in Jeffrey C. Stone v. Greenberg Traurig LLP, et al. These lawsuits arose out of the bankruptcy of Mortgages Ltd., a mortgage lender to developers in the Phoenix, Arizona area. Various other professional firms and individuals not related to the Company were also named defendants in these lawsuits. The lawsuits asserted claims for, among others things, violations of the Arizona Securities Act, common law fraud, and negligent misrepresentation, and sought to hold the CBIZ Parties vicariously liable for Mayer Hoffman’s conduct as Mortgage Ltd.’s auditor, as either a statutory control person under the Arizona Securities Act or a joint venturer under Arizona common law. With the exception of claims being pursued by two plaintiffs from the Ashkenazi lawsuit (“Baldino Group”), all other related matters have been dismissed or settled without payment by the CBIZ Parties. The Baldino Group’s claims, which allege damages of approximately $16.0 million, are currently pending, though no trial date has been set. On September 16, 2016, CBIZ, Inc. and its subsidiary CBIZ Benefits & Insurance Services, Inc. (“CBIZ Benefits”) were named as defendants in a lawsuit filed in the U.S. District Court for the Western District of Pennsylvania. The federal court case is brought by UPMC, d/b/a University of Pittsburgh Medical Center, and a health system it acquired, UPMC Altoona (formerly, Altoona Regional Health System). The lawsuit asserts professional negligence, breach of contract, and negligent misrepresentation claims against CBIZ, CBIZ Benefits and a former employee of CBIZ Benefits in connection with actuarial services provided by CBIZ Benefits to Altoona Regional Health System. The plaintiff now seeks compensatory damages of between $124.0 million and $266.0 million, plus punitive damages. The Court denied CBIZ Benefits’ motion for a summary judgment and trial is set for June 2021. On December 19, 2016, CBIZ Operations, Inc. (“CBIZ Operations”) was named as a defendant in a lawsuit filed by Zotec Partners, LLC (“Zotec”) in the Marion County Indiana Superior Court. After various amendments, the lawsuit asserts claims under Indiana law for securities, statutory and common law fraud or deception, unjust enrichment, breach of contract, and vicarious liability against CBIZ Operations and a former employee of CBIZ MMP in connection with the sale of the CBIZ MMP medical billing practice to Zotec. The plaintiff claims that CBIZ Operations had a duty to disclose the fact, unknown to employees of CBIZ Operations at the time of the transaction, that the former employee had a financial arrangement with a Zotec vendor at the time CBIZ Operations sold CBIZ MMP to Zotec. The plaintiff is now seeking damages of up to $177.0 million out of the $200.0 million transaction price. Trial is scheduled for October 2021. We cannot predict the outcome of the above matters or estimate the possible loss or range of possible loss, if any. Although the proceedings are subject to uncertainties inherent in the litigation process and the ultimate disposition of these proceedings is not presently determinable, we intend to vigorously defend these cases. In addition to those items disclosed above, we are, from time to time, subject to claims and lawsuits arising in the ordinary course of business.

Financial Instruments

Financial Instruments	3 Months Ended
	Mar. 31, 2021
Investments, All Other Investments [Abstract]
Financial Instruments	FINANCIAL INSTRUMENTS Available-For-Sale Debt Securities - In connection with certain services provided by our payroll operations, we collect funds from our clients’ accounts in advance of paying client obligations. These funds held for clients are segregated and invested in accordance with our investment policy, which requires all investments carry an investment grade rating at the time of initial investment. These investments, primarily consisting of corporate and municipal bonds, are classified as available-for-sale and are included in the “Funds held for clients” line item on the accompanying Condensed Consolidated Balance Sheets. The par value of these investments totaled $21.8 million and $24.9 million at March 31, 2021 and December 31, 2020, respectively, and had maturity or callable dates ranging from April 2021 through November 2024. At March 31, 2021, unrealized losses on the securities were not material and have not been recognized as a credit loss because the bonds are investment grade quality and management is not required or does not intend to sell prior to an expected recovery in value. The bond issuers continue to make timely principal and interest payments. The following table summarizes activities related to these investments for the three months ended March 31, 2021 and the twelve months ended December 31, 2020 (in thousands): Three Months Ended March 31, 2021 Twelve Months Ended December 31, 2020 Fair value at beginning of period $ 25,708 $ 60,659 Purchases — 3,447 Sales (1,490) (22,078) Maturities and calls (1,600) (15,409) Change in bond premium (83) (857) Fair market value adjustment (142) (54) Fair value at end of period $ 22,393 $ 25,708 Interest Rate Swaps - We utilize interest rate swaps to manage interest rate risk exposure associated with our floating-rate debt under the 2018 credit facility, or the forecasted acquisition of such liability. We do not purchase or hold any derivative instruments for trading or speculative purposes. Refer to the Annual Report on Form 10-K for the year ended December 31, 2020 for further discussion on our interest rate swaps. During the first quarter of 2021, one interest rate swap expired with a notional value of $10.0 million. As of March 31, 2021, we have three interest rate swaps outstanding. Under the terms of the interest rate swaps, we pay interest at a fixed rate of interest plus applicable margin as stated in the agreement, and receive interest that varies with the one-month LIBOR. The notional value, fixed rate of interest and expiration date of each interest rate swap as of March 31, 2021 was (i) $20.0 million – 1.770% - May 2022, (ii) $15.0 million – 2.640% - June 2023 and (iii) $50.0 million - 0.885% - April 2025. Refer to Note 7. Fair Value Measurements, for additional disclosures regarding fair value measurements. The following table summarizes our outstanding interest rate swaps and their classification in the accompanying Condensed Consolidated Balance Sheets at March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Notional Fair Balance Sheet Location Interest rate swaps $ 85,000 $ (1,299) Other non-current liabilities December 31, 2020 Notional Fair Balance Sheet Location Interest rate swap $ 10,000 $ (13) Other current liability Interest rate swaps $ 85,000 $ (2,552) Other non-current liabilities The following table summarizes the effects of the interest rate swaps on the accompanying Condensed Consolidated Statements of Comprehensive Income for the three months ended March 31, 2021 and 2020 (in thousands): Gain (Loss) Recognized Loss Reclassified Three Months Ended Three Months Ended 2021 2020 2021 2020 Interest rate swap $ 961 $ (653) $ (285) $ (34)

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The following table summarizes our assets and (liabilities) at March 31, 2021 and December 31, 2020, respectively, that are measured at fair value on a recurring basis subsequent to initial recognition and indicates the fair value hierarchy of the valuation techniques utilized by us to determine such fair value (in thousands): Level March 31, 2021 December 31, 2020 Deferred compensation plan assets 1 $ 133,478 $ 127,332 Available-for-sale debt securities 1 22,393 25,708 Deferred compensation plan liabilities 1 (133,478) (127,332) Interest rate swaps 2 (1,299) (2,565) Contingent purchase price liabilities 3 (54,230) (54,391) During the three months ended March 31, 2021 and 2020, there were no transfers between the valuation hierarchy Levels 1, 2 and 3. The following table summarizes the change in Level 3 fair values of our contingent purchase price liabilities for the three months ended March 31, 2021 and 2020 (pre-tax basis) (in thousands): 2021 2020 Beginning balance – January 1 $ (54,391) $ (32,089) Additions from business acquisitions (1,622) (4,670) Settlement of contingent purchase price liabilities 2,443 3,394 Change in fair value of contingencies (279) 875 Change in net present value of contingencies (381) (191) Ending balance – March 31 $ (54,230) $ (32,681) Contingent purchase price liabilities result from our business acquisitions and are recorded at fair value at the time of acquisition and are presented as “Contingent purchase price liability — current” and “Contingent purchase price liability — non-current” in the accompanying Condensed Consolidated Balance Sheets. We estimate the fair value of our contingent purchase price liabilities using a probability-weighted discounted cash flow model. This fair value measure is based on significant inputs not observed in the market and thus represents a Level 3 measurement. Fair value measurements characterized within Level 3 of the fair value hierarchy are measured based on unobservable inputs that are supported by little or no market activity and reflect our own assumptions in measuring fair value. We probability weight risk-adjusted estimates of future performance of acquired businesses, then calculate the contingent purchase price based on the estimates and discount them to present value representing management’s best estimate of fair value. The fair value of the contingent purchase price liabilities are reassessed quarterly based on assumptions provided by practice group leaders and business unit controllers together with our corporate finance department. Any change in the fair value estimate is recorded in the earnings of that period. Refer to Note 11. Business Combinations, for further discussion of our acquisitions and contingent purchase price liabilities. The carrying amounts of our cash and cash equivalents, accounts receivable and accounts payable approximate fair value because of the short maturity of these instruments, and the carrying value of bank debt approximates fair value as the interest rate on the bank debt is variable and approximates current market rates. As a result, the fair value measurement of our bank debt is considered to be Level 2.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Other Comprehensive Income (Loss)	OTHER COMPREHENSIVE INCOME (LOSS)The following table is a summary of other comprehensive income (loss) and discloses the tax impact of each component of other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended 2021 2020 Net unrealized loss on available-for-sale securities, net of income taxes (1) $ (103) $ (587) Net unrealized gain (loss) on interest rate swaps, net of income taxes (2) 961 (653) Foreign currency translation (4) (12) Total other comprehensive income (loss) $ 854 $ (1,252) (1) Net of income tax benefit of $39 and $210 for the three months ended March 31, 2021 and 2020, respectively. (2) Net of income tax expense of $310 and income tax benefit of $210 for the three months ended March 31, 2021 and 2020, respectively.

Employee Stock Plans

Employee Stock Plans	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Employee Stock Plans	EMPLOYEE STOCK PLANS The 2019 Stock Omnibus Incentive Plan (the “2019 Plan”), which expires in 2029, permits the grant of various forms of stock-based awards. The terms and vesting schedules for the stock-based awards vary by type and date of grant. A maximum of 3.1 million stock options, restricted stock or other stock-based compensation awards may be granted. Shares subject to award under the 2019 Plan may be either authorized but unissued shares of our common stock or treasury shares. Refer to the Annual Report on Form 10-K for the year ended December 31, 2020 for further discussion on the 2019 Plan. Compensation expense for stock-based awards recognized during the three months ended March 31, 2021 and 2020 was as follows (in thousands): Three Months Ended 2021 2020 Stock options $ 301 $ 421 Restricted stock units and awards 1,381 1,171 Performance share units 1,173 431 Total stock-based compensation expense $ 2,855 $ 2,023 Stock Options and Restricted Stock Units and Awards – The following table presents our stock options and restricted stock units and awards activity during the three months ended March 31, 2021 (in thousands, except per share data): Stock Options Restricted Stock Units and Awards Number of Weighted Average Exercise Price Per Share Number of Weighted Average Grant-Date Fair Value (1) Outstanding at beginning of year 1,820 $ 15.02 461 $ 21.03 Granted — $ — 140 $ 27.56 Exercised or released (397) $ 11.10 (99) $ 22.38 Expired or canceled — $ — — $ — Outstanding at March 31, 2021 1,423 $ 16.12 502 $ 22.58 Exercisable at March 31, 2021 978 $ 15.19 (1) Represents weighted average market value of the shares; awards are granted at no cost to the recipients. Performance Share Units (“PSUs”) – PSUs are earned based on our financial performance over a contractual term of three years and the associated expense is recognized over that period based on the fair value of the award. A three-year cliff vesting schedule of the PSUs is dependent upon the Company’s performance relative to pre-established goals based on an earnings per share target (weighted 70%) and total growth in revenue (weighted 30%). The fair value of PSUs is calculated using the market value of a share of our common stock on the date of grant. For performance achieved above specified levels, the recipient may earn additional shares of stock, not to exceed 200% of the number of PSUs initially granted. The following table presents our PSU award activity during the three months ended March 31, 2021 (in thousands, except per share data): Performance Weighted Outstanding at beginning of year 307 $ 22.18 Granted 140 $ 27.56 Vested — $ — Adjustments for performance results — $ — Canceled — $ — Outstanding at March 31, 2021 447 $ 23.86

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE The following table sets forth the computation of basic and diluted earnings per share from continuing operations for the three months ended March 31, 2021 and 2020 (in thousands, except per share data). Three Months Ended 2021 2020 Numerator: Income from continuing operations $ 50,216 $ 36,862 Denominator: Basic Weighted average common shares outstanding 53,366 54,571 Diluted Stock options (1) 776 993 Restricted stock awards (1) 257 296 Contingent shares (2) 37 85 Diluted weighted average common shares outstanding (3) 54,436 55,945 Basic earnings per share from continuing operations $ 0.94 $ 0.68 Diluted earnings per share from continuing operations $ 0.92 $ 0.66 (1) A total of 1 thousand and 33 thousand stock-based awards were excluded from the calculation of diluted earnings per share for the three months ended March 31, 2021 and 2020. respectively, as their effect would be anti-dilutive. (2) Contingent shares represent additional shares to be issued for purchase price earned by former owners of businesses acquired by us once future considerations have been met. Refer to Note 11. Business Combinations, for further details. (3) The denominator used in calculating diluted earnings per share did not include 447 thousand and 332 thousand performance share units for the three months ended March 31, 2021 and 2020, respectively. The performance conditions associated with these performance share

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
Business Combinations	BUSINESS COMBINATIONS Our acquisition strategy focuses on businesses with a leadership team that is committed to best in class culture, extraordinary client service and cross-serving potential. CBIZ has a long history of acquiring businesses that share common cultural values with us and provide value-added services to the small and midsize business market. The valuation of any business is a subjective process and includes industry, geography, profit margins, expected cash flows, client retention, nature of recurring or non-recurring project-based work, growth rate assumptions and competitive market conditions. During the three months ended March 31, 2021, we completed the following acquisition: • Effective January 1, 2021, we acquired substantially all the assets of Middle Market Advisory Group (“MMA”). MMA, based in Englewood, CO, is a provider of tax compliance and consulting services to middle market companies and family groups in the real estate, automotive, technology and SAAS, construction, and manufacturing industries. Operating results will be reported in the Financial Services practice group. Aggregate consideration for the acquisition consisted of approximately $1.9 million in cash and $1.6 million in contingent consideration. Under the terms of the acquisition agreement, a portion of the purchase price is contingent on future performance of the business acquired. The maximum potential undiscounted amount of all future payments for the 2021 acquisition that we could be required to make under the contingent arrangements is $1.7 million. As of March 31, 2021, the aggregated fair value of contingent consideration related to this acquisition was $1.6 million, of which $0.6 million was recorded in Contingent purchase price liability – current and $1.0 million was recorded in Contingent purchase price liability – non-current in the accompanying Condensed Consolidated Balance Sheets at March 31, 2021. Refer to Note 7. Fair Value Measurements, for additional information regarding contingent purchase price liability fair value and fair value adjustments. Annualized revenue from the acquired business is estimated to be approximately $3.6 million. Pro forma results of operations for this acquisition has not been presented because the effects of the acquisitions were not significant to our Income from continuing operations before income taxes. During the three months ended March 31, 2020, we have acquired substantially all of the assets of the following businesses: • Effective February 1, 2020, we acquired substantially all the assets of Alliance Insurance Services, Inc., a provider of insurance and advisory services based in Washington, DC. Operating results will be reported in the Benefits and Insurance Services practice group. • Effective February 1, 2020, we acquired substantially all the assets of Pension Dynamics Company, LLC, a full-service retirement and benefits plan advisor based in Pleasant Hill, California. Operating results will be reported in the Benefits and Insurance Services practice group. • Effective February 1, 2020, we acquired substantially all the assets of Sunshine Systems, a payroll solutions provider based in Massachusetts. Operating results will be reported in the Benefits and Insurance Services practice group. Aggregated consideration for these acquisitions consisted of approximately $9.4 million in cash, $0.9 million in our common stock, and $4.8 million in contingent considerations. Under the terms of the acquisition agreements, a portion of the purchase price is contingent on future performance of the business acquired. The maximum potential undiscounted amount of all future payments that we could be required to make under the contingent arrangements is $6.2 million. As of March 31, 2020, the aggregated fair value of the contingent considerations related to these acquisitions was $4.7 million, of which $2.0 million was recorded in "Contingent purchase price liability – current" and $2.7 million was recorded in "Contingent purchase price liability – non-current" in the accompanying Condensed Consolidated Balance Sheets at March 31, 2020. Refer to Note 7. Fair Value Measurements, for additional information regarding contingent purchase price liability fair value and fair value adjustments. Annualized revenue from the acquired businesses is estimated to be approximately $6.1 million. Pro forma results of operations for these acquisitions have not been presented because the effects of these acquisitions were not material to our "Income from continuing operations before income taxes." The goodwill of $1.5 million and $11.2 million arising from the acquisitions for the three months ended March 31, 2021 and 2020, respectively, primarily results from expected future earnings and cash flows from the existing management team, as well as the synergies created by the integration of the new business within our organization, including cross-selling opportunities expected with our Financial Services practice group and the Benefits and Insurance Services practice group, to help strengthen our existing service offerings and expand our market position. All of the goodwill is deductible for income tax purposes. Acquisition of Client Lists - During the three months ended March 31, 2021, we purchased one client list reported in the Benefits and Insurance Services practice group for $0.2 million, of which $0.1 million is contingent. During the three months ended March 31, 2020, we purchased two client lists, reported in the Benefits and Insurance Services practice group, for total consideration of $0.5 million, of which $0.3 million is contingent. Change in Contingent Purchase Price Liability for Previous Acquisitions - During the three months ended March 31, 2021 and 2020, the fair value of the contingent purchase price liability related to prior acquisitions increased by $0.7 million and decreased by $0.7 million, respectively. The change in fair value during the three months ended March 31, 2021 is mostly attributable to the change in stock price related to the mark-to-market adjustment of future common stock issuances and net present value adjustments. The change in fair value during the three months ended March 31, 2020 is due to the change in stock price related to the mark-to-market adjustment of future common stock issuances offset by net present value adjustments. These adjustments are included in "Other income (expense), net" in the accompanying Condensed Consolidated Statements of Comprehensive Income. Contingent Payments for Previous Business Acquisitions and Client Lists - We paid $1.5 million in cash and issued approximately 0.1 million shares of our common stock during the three months ended March 31, 2021 for previous acquisitions. For the same period in 2020, we paid $2.4 million in cash and issued approximately 0.1 million shares of our common stock for previous acquisitions. During the three months ended March 31, 2021 and 2020, we paid approximately $0.1 million and $0.3 million, respectively, in cash for previous client list purchases.

Segment Disclosures

Segment Disclosures	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Segment Disclosures	SEGMENT DISCLOSURES Our business units have been aggregated into three practice groups: Financial Services, Benefits and Insurance Services and National Practices. The business units have been aggregated based on the following factors: similarity of the products and services provided to clients; similarity of the regulatory environment in which they operate; and similarity of economic conditions affecting long-term performance. The business units are managed along these segment lines. A general description of services provided by each practice group is provided in the table below. Financial Services Benefits and Insurance Services National Practices Accounting and Tax Group Health Benefits Consulting Managed Networking and Hardware Services Government Healthcare Consulting Payroll Healthcare Consulting Financial Advisory Property and Casualty Valuation Retirement Plan Services Risk & Advisory Services Corporate and Other . Included in “Corporate and Other” are operating expenses that are not directly allocated to the individual business units. These expenses are primarily comprised of certain health care costs, gains or losses attributable to assets held in our non-qualified deferred compensation plan, stock-based compensation, consolidation and integration charges, certain professional fees, certain advertising costs and other various expenses. Accounting policies of the practice groups are the same as those described in Note 1. Basis of Presentation and Significant Accounting Policies, to the Annual Report on Form 10-K for the year ended December 31, 2020. Upon consolidation, intercompany accounts and transactions are eliminated, thus inter-segment revenue is not included in the measure of profit or loss for the practice groups. Performance of the practice groups is evaluated on operating income excluding those costs listed above, which are reported in the “Corporate and Other” segment. Segment information for the three months ended March 31, 2021 and 2020 is presented below. We do not manage our assets on a segment basis, therefore segment assets are not presented below. The following table disaggregates our revenue by source (in thousands): Three Months Ended March 31, 2021 Financial Benefits & National Consolidated Accounting, tax, advisory and consulting $ 204,149 — — $ 204,149 Core benefits and insurance services — 84,070 — 84,070 Non-core benefits and insurance services — 3,169 — 3,169 Managed networking, hardware services — — 6,895 6,895 National practices consulting — — 2,447 2,447 Total revenue $ 204,149 $ 87,239 $ 9,342 $ 300,730 Three Months Ended March 31, 2020 Financial Benefits & National Consolidated Accounting, tax, advisory and consulting $ 188,777 — — $ 188,777 Core benefits and insurance services — 76,472 — 76,472 Non-core benefits and insurance services — 3,140 — 3,140 Managed networking, hardware services — — 6,575 6,575 National practices consulting — — 2,491 2,491 Total revenue $ 188,777 $ 79,612 $ 9,066 $ 277,455 Segment information for the three months ended March 31, 2021 and 2020 was as follows (in thousands): Three Months Ended March 31, 2021 Financial Benefits National Corporate Total Revenue $ 204,149 $ 87,239 $ 9,342 $ — $ 300,730 Operating expenses 141,746 66,933 8,541 6,751 223,971 Gross margin 62,403 20,306 801 (6,751) 76,759 Corporate general and administrative expenses — — — 14,483 14,483 Operating income (loss) 62,403 20,306 801 (21,234) 62,276 Other income (expense): Interest expense — — — (877) (877) Other income, net 98 174 — 4,517 4,789 Total other income (expense), net 98 174 — 3,640 3,912 Income (loss) from continuing operations before income tax expense $ 62,501 $ 20,480 $ 801 $ (17,594) $ 66,188 Three Months Ended March 31, 2020 Financial Benefits National Corporate Total Revenue $ 188,777 $ 79,612 $ 9,066 $ — $ 277,455 Operating expenses 138,598 65,223 8,283 (12,277) 199,827 Gross margin 50,179 14,389 783 12,277 77,628 Corporate general and administrative expenses — — — 10,489 10,489 Operating income (loss) 50,179 14,389 783 1,788 67,139 Other income (expense): Interest expense — (11) — (1,108) (1,119) Gain on sale of operations, net 40 55 — — 95 Other income (expense), net 19 96 1 (15,916) (15,800) Total other income (expense), net 59 140 1 (17,024) (16,824) Income (loss) from continuing operations before income tax expense $ 50,238 $ 14,529 $ 784 $ (15,236) $ 50,315

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Subsequent to March 31, 2021 up to April 27, 2021, we repurchased approximately 0.3 million shares of our common stock in the open market at a total cost of approximately $9.0 million. Effective April 1, 2021, we acquired substantially all the assets of Wright Retirement Services, LLC ("Wright"). Wright, located in Valdosta, Georgia, specializes in third party administration services for retirement plan sponsors. Annualized revenue is estimated to be approximately $1.2 million. Wright will be included as a component of our Benefits and Insurance practice group. On April 29, 2021, we announced the acquisition of the non-attest assets of Berntson Porter & Company, PLLC ("BP"). The acquisition is effective on May 1, 2021. Concurrent with this transaction, Mayer Hoffman McCann P.C., a national independent CPA firm with whom we maintain joint-referral relationship and administrative service agreement, acquires the attest assets of BP. Located in Bellevue, Washington, BP provides comprehensive accounting and financial consulting services including tax, forensic, economic and valuation services and transaction services. BP serves a wide range of industries with specialities including construction, real estate, hospitality, manufacturing and technology. Annualized revenue is estimated to be approximately $26.0 million. BP will be included as a component of our Financial Services practice group.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Description of Business	Description of Business: CBIZ, Inc. is a diversified services company which, acting through its subsidiaries, has been providing professional business services since 1996, primarily to small and medium-sized businesses, as well as individuals, governmental entities, and not-for-profit enterprises throughout the United States and parts of Canada. CBIZ, Inc. manages and reports its operations along three practice groups: Financial Services, Benefits and Insurance Services and National Practices. A further description of products and services offered by each of the practice groups is provided in Note 12. Segment Disclosures, to the accompanying condensed consolidated financial statements.
Basis of Consolidation	Basis of Consolidation: The accompanying unaudited condensed consolidated financial statements include the operations of CBIZ, Inc. and all of its wholly-owned subsidiaries (“CBIZ”, the “Company”, “we”, “us”, or “our”), after elimination of all intercompany balances and transactions. These condensed consolidated financial statements do not reflect the operations or accounts of variable interest entities as the impact is not material to the financial condition, results of operations or cash flows of CBIZ.
Unaudited Interim Financial Statements	Unaudited Interim Financial Statements: The condensed consolidated financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this quarterly report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020. In the opinion of CBIZ management, the accompanying condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the financial condition, results of operations, and cash flows for the interim periods presented, but are not necessarily indicative of the results of operations to be anticipated for the full year ending December 31, 2021.
Use of Estimates	Use of Estimates: The preparation of condensed consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Changes in circumstances could cause actual results to differ materially from these estimates.
Changes in Accounting Policies	Changes in Accounting Policies: We have consistently applied the accounting policies for the periods presented as described in Note 1, Basis of Presentation and Significant Accounting Policies, to the consolidated financial statements contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020.
New Accounting Pronouncements	NEW ACCOUNTING PRONOUNCEMENTSThe FASB ASC is the sole source of authoritative GAAP other than the SEC issued rules and regulations that apply only to SEC registrants. The FASB issues an accounting standard to communicate changes to the FASB codification. We assess and review the impact of all accounting standards. Any accounting standards not listed below were reviewed and determined to be either not applicable or are not expected to have a material impact on the consolidated financial statements of the Company. Accounting Standards Issued But Not Yet Adopted Reference Rate Reform : In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting , which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments in this ASU are effective for all entities through December 31, 2022. We are currently evaluating the effect of this new standard on our consolidated financial statements and have not adopted any of the transition relief available under the new guidance as of March 31, 2021. Subsequently, in January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848): Scope

Accounts Receivable, Net (Table

Accounts Receivable, Net (Tables)	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
Schedule of Accounts Receivable, Net	Accounts receivable, net, at March 31, 2021 and December 31, 2020 were as follows (in thousands): March 31, December 31, Trade accounts receivable $ 177,104 $ 167,575 Unbilled revenue, at net realizable value 106,662 63,494 Total accounts receivable 283,766 231,069 Allowance for doubtful accounts (13,156) (14,894) Accounts receivable, net $ 270,610 $ 216,175
Schedule of Changes in the Allowance for Doubtful Accounts on Accounts Receivable	Changes to the allowance for doubtful accounts for the three months ended March 31, 2021 and twelve months ended December 31, 2020 are as follows (in thousands): March 31, December 31, 2020 Balance at beginning of period $ (14,894) $ (14,379) Provision (390) (9,323) Charge-offs, net of recoveries 2,128 8,808 Allowance for doubtful accounts $ (13,156) $ (14,894)

Debt and Financing Arrangemen_2

Debt and Financing Arrangements (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Summary of Unsecured Credit Facility	Effective interest rates, including the impact of interest rate swaps associated with the 2018 credit facility, were as follows: Three Months Ended 2021 2020 Weighted average rates 2.10% 2.50% Range of effective rates 1.08% - 3.64% 1.61% - 4.75%
Summary of Recognized Interest Expense	Interest expense, including amortization of deferred financing costs, commitment fees, line of credit fees, and other applicable bank charges, was as follows (in thousands): Three Months Ended March 31, 2021 2020 2018 credit facility $ 871 $ 1,101 Other line of credit — 1 Other 6 17 Total $ 877 $ 1,119

Financial Instruments (Tables)

Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2021
Investments, All Other Investments [Abstract]
Summary of Investments	The following table summarizes activities related to these investments for the three months ended March 31, 2021 and the twelve months ended December 31, 2020 (in thousands): Three Months Ended March 31, 2021 Twelve Months Ended December 31, 2020 Fair value at beginning of period $ 25,708 $ 60,659 Purchases — 3,447 Sales (1,490) (22,078) Maturities and calls (1,600) (15,409) Change in bond premium (83) (857) Fair market value adjustment (142) (54) Fair value at end of period $ 22,393 $ 25,708
Summary of Outstanding Interest Rate Swaps	The following table summarizes our outstanding interest rate swaps and their classification in the accompanying Condensed Consolidated Balance Sheets at March 31, 2021 and December 31, 2020 (in thousands): March 31, 2021 Notional Fair Balance Sheet Location Interest rate swaps $ 85,000 $ (1,299) Other non-current liabilities December 31, 2020 Notional Fair Balance Sheet Location Interest rate swap $ 10,000 $ (13) Other current liability Interest rate swaps $ 85,000 $ (2,552) Other non-current liabilities
Summary of Effects of Interest Rate Swap	The following table summarizes the effects of the interest rate swaps on the accompanying Condensed Consolidated Statements of Comprehensive Income for the three months ended March 31, 2021 and 2020 (in thousands): Gain (Loss) Recognized Loss Reclassified Three Months Ended Three Months Ended 2021 2020 2021 2020 Interest rate swap $ 961 $ (653) $ (285) $ (34)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following table summarizes our assets and (liabilities) at March 31, 2021 and December 31, 2020, respectively, that are measured at fair value on a recurring basis subsequent to initial recognition and indicates the fair value hierarchy of the valuation techniques utilized by us to determine such fair value (in thousands): Level March 31, 2021 December 31, 2020 Deferred compensation plan assets 1 $ 133,478 $ 127,332 Available-for-sale debt securities 1 22,393 25,708 Deferred compensation plan liabilities 1 (133,478) (127,332) Interest rate swaps 2 (1,299) (2,565) Contingent purchase price liabilities 3 (54,230) (54,391)
Change in Level 3 Fair Values of Contingent Purchase Price Liabilities	During the three months ended March 31, 2021 and 2020, there were no transfers between the valuation hierarchy Levels 1, 2 and 3. The following table summarizes the change in Level 3 fair values of our contingent purchase price liabilities for the three months ended March 31, 2021 and 2020 (pre-tax basis) (in thousands): 2021 2020 Beginning balance – January 1 $ (54,391) $ (32,089) Additions from business acquisitions (1,622) (4,670) Settlement of contingent purchase price liabilities 2,443 3,394 Change in fair value of contingencies (279) 875 Change in net present value of contingencies (381) (191) Ending balance – March 31 $ (54,230) $ (32,681)

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Summary of Other Comprehensive Loss and Tax Impact	The following table is a summary of other comprehensive income (loss) and discloses the tax impact of each component of other comprehensive income (loss) for the three months ended March 31, 2021 and 2020 (in thousands): Three Months Ended 2021 2020 Net unrealized loss on available-for-sale securities, net of income taxes (1) $ (103) $ (587) Net unrealized gain (loss) on interest rate swaps, net of income taxes (2) 961 (653) Foreign currency translation (4) (12) Total other comprehensive income (loss) $ 854 $ (1,252) (1) Net of income tax benefit of $39 and $210 for the three months ended March 31, 2021 and 2020, respectively. (2) Net of income tax expense of $310 and income tax benefit of $210 for the three months ended March 31, 2021 and 2020, respectively.

Employee Stock Plans (Tables)

Employee Stock Plans (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Stock-Based Compensation Awards	Compensation expense for stock-based awards recognized during the three months ended March 31, 2021 and 2020 was as follows (in thousands): Three Months Ended 2021 2020 Stock options $ 301 $ 421 Restricted stock units and awards 1,381 1,171 Performance share units 1,173 431 Total stock-based compensation expense $ 2,855 $ 2,023
Schedule of Stock Options, Restricted Stock Units and Awards, and Performance Share Units Award Activity	The following table presents our stock options and restricted stock units and awards activity during the three months ended March 31, 2021 (in thousands, except per share data): Stock Options Restricted Stock Units and Awards Number of Weighted Average Exercise Price Per Share Number of Weighted Average Grant-Date Fair Value (1) Outstanding at beginning of year 1,820 $ 15.02 461 $ 21.03 Granted — $ — 140 $ 27.56 Exercised or released (397) $ 11.10 (99) $ 22.38 Expired or canceled — $ — — $ — Outstanding at March 31, 2021 1,423 $ 16.12 502 $ 22.58 Exercisable at March 31, 2021 978 $ 15.19 (1) Represents weighted average market value of the shares; awards are granted at no cost to the recipients. The following table presents our PSU award activity during the three months ended March 31, 2021 (in thousands, except per share data): Performance Weighted Outstanding at beginning of year 307 $ 22.18 Granted 140 $ 27.56 Vested — $ — Adjustments for performance results — $ — Canceled — $ — Outstanding at March 31, 2021 447 $ 23.86

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Share from Continuing Operations	The following table sets forth the computation of basic and diluted earnings per share from continuing operations for the three months ended March 31, 2021 and 2020 (in thousands, except per share data). Three Months Ended 2021 2020 Numerator: Income from continuing operations $ 50,216 $ 36,862 Denominator: Basic Weighted average common shares outstanding 53,366 54,571 Diluted Stock options (1) 776 993 Restricted stock awards (1) 257 296 Contingent shares (2) 37 85 Diluted weighted average common shares outstanding (3) 54,436 55,945 Basic earnings per share from continuing operations $ 0.94 $ 0.68 Diluted earnings per share from continuing operations $ 0.92 $ 0.66 (1) A total of 1 thousand and 33 thousand stock-based awards were excluded from the calculation of diluted earnings per share for the three months ended March 31, 2021 and 2020. respectively, as their effect would be anti-dilutive. (2) Contingent shares represent additional shares to be issued for purchase price earned by former owners of businesses acquired by us once future considerations have been met. Refer to Note 11. Business Combinations, for further details. (3) The denominator used in calculating diluted earnings per share did not include 447 thousand and 332 thousand performance share units for the three months ended March 31, 2021 and 2020, respectively. The performance conditions associated with these performance share

Segment Disclosures (Tables)

Segment Disclosures (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Summary of Disaggregation of Revenue by Source	The following table disaggregates our revenue by source (in thousands): Three Months Ended March 31, 2021 Financial Benefits & National Consolidated Accounting, tax, advisory and consulting $ 204,149 — — $ 204,149 Core benefits and insurance services — 84,070 — 84,070 Non-core benefits and insurance services — 3,169 — 3,169 Managed networking, hardware services — — 6,895 6,895 National practices consulting — — 2,447 2,447 Total revenue $ 204,149 $ 87,239 $ 9,342 $ 300,730 Three Months Ended March 31, 2020 Financial Benefits & National Consolidated Accounting, tax, advisory and consulting $ 188,777 — — $ 188,777 Core benefits and insurance services — 76,472 — 76,472 Non-core benefits and insurance services — 3,140 — 3,140 Managed networking, hardware services — — 6,575 6,575 National practices consulting — — 2,491 2,491 Total revenue $ 188,777 $ 79,612 $ 9,066 $ 277,455
Summary of Segment Information	Segment information for the three months ended March 31, 2021 and 2020 was as follows (in thousands): Three Months Ended March 31, 2021 Financial Benefits National Corporate Total Revenue $ 204,149 $ 87,239 $ 9,342 $ — $ 300,730 Operating expenses 141,746 66,933 8,541 6,751 223,971 Gross margin 62,403 20,306 801 (6,751) 76,759 Corporate general and administrative expenses — — — 14,483 14,483 Operating income (loss) 62,403 20,306 801 (21,234) 62,276 Other income (expense): Interest expense — — — (877) (877) Other income, net 98 174 — 4,517 4,789 Total other income (expense), net 98 174 — 3,640 3,912 Income (loss) from continuing operations before income tax expense $ 62,501 $ 20,480 $ 801 $ (17,594) $ 66,188 Three Months Ended March 31, 2020 Financial Benefits National Corporate Total Revenue $ 188,777 $ 79,612 $ 9,066 $ — $ 277,455 Operating expenses 138,598 65,223 8,283 (12,277) 199,827 Gross margin 50,179 14,389 783 12,277 77,628 Corporate general and administrative expenses — — — 10,489 10,489 Operating income (loss) 50,179 14,389 783 1,788 67,139 Other income (expense): Interest expense — (11) — (1,108) (1,119) Gain on sale of operations, net 40 55 — — 95 Other income (expense), net 19 96 1 (15,916) (15,800) Total other income (expense), net 59 140 1 (17,024) (16,824) Income (loss) from continuing operations before income tax expense $ 50,238 $ 14,529 $ 784 $ (15,236) $ 50,315

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2021practiceGroup
Accounting Policies [Abstract]
Number of practice groups	3

Accounts Receivable, Net - Sche

Accounts Receivable, Net - Schedule of Accounts Receivables Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Trade accounts receivable	$ 177,104	$ 167,575
Unbilled revenue, at net realizable value	106,662	63,494
Total accounts receivable	283,766	231,069
Allowance for doubtful accounts	(13,156)	(14,894)	$ (14,379)
Accounts receivable, net	$ 270,610	$ 216,175

Accounts Receivable, Net - Sc_2

Accounts Receivable, Net - Schedule of Changes in the Allowance for Doubtful Accounts on Accounts Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ (14,894)	$ (14,379)
Provision	(390)	(9,323)
Charge-offs, net of recoveries	2,128	8,808
Allowance for doubtful accounts	$ (13,156)	$ (14,894)

Debt and Financing Arrangemen_3

Debt and Financing Arrangements - Additional Information (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Outstanding balance under applicable credit facility	$ 162,000,000	$ 108,000,000
Outstanding letters of credit	3,000,000	1,700,000
Other line of credit
Debt Instrument [Line Items]
Revolving loan commitment	20,000,000
Outstanding line of credit	0
2018 Credit Facility
Debt Instrument [Line Items]
Unsecured credit facility	400,000,000
Outstanding balance under applicable credit facility	162,000,000	$ 108,000,000
Available funds under credit facility	228,700,000
Outstanding letters of credit	$ 3,000,000

Debt and Financing Arrangemen_4

Debt and Financing Arrangements - Summary of Unsecured Credit Facility (Details)	Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Weighted average rates	2.10%	2.50%
Minimum
Debt Instrument [Line Items]
Range of effective rates	1.08%	1.61%
Maximum
Debt Instrument [Line Items]
Range of effective rates	3.64%	4.75%

Debt and Financing Arrangemen_5

Debt and Financing Arrangements - Summary of Recognized Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Total	$ 877	$ 1,119
2018 credit facility
Debt Instrument [Line Items]
Total	871	1,101
Other line of credit
Debt Instrument [Line Items]
Total	0	1
Other
Debt Instrument [Line Items]
Total	$ 6	$ 17

Commitments and Contingencies -

Commitments and Contingencies - Letters of Credit and Guarantees (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Letters of credit outstanding	$ 3	$ 1.7
License bonds outstanding amount	$ 2.3	$ 2.2

Commitments and Contingencies_2

Commitments and Contingencies - Legal Proceedings (Details) $ in Millions	Dec. 19, 2016USD ($)	Sep. 16, 2016USD ($)	Mar. 31, 2021USD ($)plaintiff
Baldino Group
Commitments And Contingencies [Line Items]
Number of plaintiffs | plaintiff			2
Damages sought amount			$ 16
Altoona Regional Health System | Minimum
Commitments And Contingencies [Line Items]
Damages sought amount		$ 124
Altoona Regional Health System | Maximum
Commitments And Contingencies [Line Items]
Damages sought amount		$ 266
CBIZ Operations and a former employee of CBIZ MMP
Commitments And Contingencies [Line Items]
Total transaction price	$ 200
CBIZ Operations and a former employee of CBIZ MMP | Maximum
Commitments And Contingencies [Line Items]
Damages sought amount	$ 177

Financial Instruments - Availab

Financial Instruments - Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Investments, All Other Investments [Abstract]
Par value of available-for-sale debt securities	$ 21.8	$ 24.9

Financial Instruments - Summary

Financial Instruments - Summary of Investments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available for Sale [Roll Forward]
Fair value at beginning of period	$ 25,708	$ 60,659
Purchases	0	3,447
Sales	(1,490)	(22,078)
Maturities and calls	(1,600)	(15,409)
Change in bond premium	(83)	(857)
Fair market value adjustment	(142)	(54)
Fair value at end of period	$ 22,393	$ 25,708

Financial Instruments - Interes

Financial Instruments - Interest Rate Swaps (Details)	Mar. 31, 2021USD ($)swap
Interest rate swaps
Debt Securities, Available-for-sale [Line Items]
Number of interest rate swaps expired | swap	1
Number of interest rate swaps outstanding | swap	3
Interest rate swap, February 2021 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 10,000,000
Interest rate swap, May 2022 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 20,000,000
Interest rate swap, fixed interest rate	1.77%
Interest rate swap, June 2023 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 15,000,000
Interest rate swap, fixed interest rate	2.64%
Interest rate swap, April 2025 expiration
Debt Securities, Available-for-sale [Line Items]
Notional amount	$ 50,000,000
Interest rate swap, fixed interest rate	0.885%

Financial Instruments - Summa_2

Financial Instruments - Summary of Outstanding Interest Rate Swaps (Details) - Interest rate swaps - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Other non-current liabilities
Derivatives, Fair Value [Line Items]
Notional amount, liability	$ 85,000,000	$ 85,000,000
Fair value, liability	$ (1,299,000)	(2,552,000)
Other current liability
Derivatives, Fair Value [Line Items]
Notional amount, liability		10,000,000
Fair value, liability		$ (13,000)

Financial Instruments - Summa_3

Financial Instruments - Summary of Effects of Interest Rate Swaps (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in AOCL, net of tax	$ 961	$ (653)
Interest rate swaps
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized in AOCL, net of tax	961	(653)
Loss Reclassified from AOCL into Expense	$ (285)	$ (34)

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	$ 133,478	$ 127,332
Available-for-sale debt securities	22,393	25,708	$ 60,659
Deferred compensation plan liabilities	(133,478)	(127,332)
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	133,478	127,332
Available-for-sale debt securities	22,393	25,708
Deferred compensation plan liabilities	(133,478)	(127,332)
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps	(1,299)	(2,565)
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent purchase price liabilities	$ (54,230)	$ (54,391)

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair value measurements, inter-transfers between levels	$ 0	$ 0

Fair Value Measurements - Chang

Fair Value Measurements - Change in Level 3 Fair Values of Contingent Purchase Price Liabilities (Details) - Contingent purchase price liabilities - Level 3 - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance – January 1	$ (54,391)	$ (32,089)
Additions from business acquisitions	(1,622)	(4,670)
Settlement of contingent purchase price liabilities	2,443	3,394
Change in fair value of contingencies	(279)	875
Change in net present value of contingencies	(381)	(191)
Ending balance - March 31	$ (54,230)	$ (32,681)

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) - Summary of Other Comprehensive Loss and Tax Impact (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Net unrealized loss on available-for-sale securities, net of income taxes	$ (103)	$ (587)
Net unrealized gain (loss) on interest rate swaps, net of income taxes	961	(653)
Foreign currency translation	(4)	(12)
Total other comprehensive income (loss)	854	(1,252)
Unrealized loss on available-for-sale securities, income tax expense (benefit)	(39)	(210)
Unrealized gain (loss) on interest rate swaps, income tax expense (benefit)	$ 310	$ (210)

Employee Stock Plans - Addition

Employee Stock Plans - Additional Information (Details) - shares shares in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2019
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, remaining contractual term	3 years
Performance share units, vesting period	3 years
Achievement of an earnings per share target	70.00%
Achievement of total growth in revenue	30.00%
Performance shares | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of initial grant	200.00%
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum stock based compensation awards granted under the plan		3.1

Employee Stock Plans - Schedule

Employee Stock Plans - Schedule of Stock-Based Compensation Awards (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock options	$ 301	$ 421
Restricted stock units and awards	1,381	1,171
Performance share units	1,173	431
Total stock-based compensation expense	$ 2,855	$ 2,023

Employee Stock Plans - Schedu_2

Employee Stock Plans - Schedule of Stock Options Award Activity (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Stock Option Activity
Outstanding at beginning of period (in shares) | shares	1,820
Granted (in shares) | shares	0
Exercised or released (in shares) | shares	(397)
Expired or canceled (in shares) | shares	0
Outstanding at end of period (in shares) | shares	1,423
Exercisable at end of period (in shares) | shares	978
Stock Option Weighted Average Exercise Price Per Share
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 15.02
Granted (in dollars per share) | $ / shares	0
Exercised or released (in dollars per share) | $ / shares	11.10
Expired or canceled (in dollars per share) | $ / shares	0
Outstanding at end of period (in dollars per share) | $ / shares	16.12
Exercisable at end of period (in dollars per share) | $ / shares	$ 15.19

Employee Stock Plans - Schedu_3

Employee Stock Plans - Schedule of Restricted Stock Units and Awards Activity (Details) - Restricted Stock Units and Awards shares in Thousands	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Restricted Stock Units and Awards Activity
Outstanding at beginning of period (in shares) | shares	461
Granted (in shares) | shares	140
Exercised or released (in shares) | shares	(99)
Expired or canceled (in shares) | shares	0
Outstanding at end of period (in shares) | shares	502
Restricted Stock Units and Awards Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 21.03
Granted (in dollars per share) | $ / shares	27.56
Exercised or released (in dollars per share) | $ / shares	22.38
Expired or canceled (in dollars per share) | $ / shares	0
Outstanding at end of period (in dollars per share) | $ / shares	$ 22.58

Employee Stock Plans - Schedu_4

Employee Stock Plans - Schedule of Performance Share Units Award Activity (Details) - Performance shares shares in Thousands	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Performance Share Units Award Activity
Outstanding at beginning of period (in shares) | shares	307
Granted (in shares) | shares	140
Vested (in shares) | shares	0
Adjustments for performance results (in shares) | shares	0
Canceled (in shares) | shares	0
Outstanding at end of period (in shares) | shares	447
Performance Share Units Award Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 22.18
Granted (in dollars per share) | $ / shares	27.56
Vested (in dollars per share) | $ / shares	0
Adjustments for performance results (in dollars per share) | $ / shares	0
Canceled (in dollars per share) | $ / shares	0
Outstanding at end of period (in dollars per share) | $ / shares	$ 23.86

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings Per Share for Continuing Operations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Income from continuing operations	$ 50,216	$ 36,862
Basic
Weighted average common shares outstanding (in shares)	53,366	54,571
Diluted
Stock options (in shares)	776	993
Restricted stock awards (in shares)	257	296
Contingent shares (in shares)	37	85
Diluted weighted average common shares outstanding (in shares)	54,436	55,945
Basic earnings per share from continuing operations (in dollars per share)	$ 0.94	$ 0.68
Diluted earnings per share from continuing operations (in dollars per share)	$ 0.92	$ 0.66
Share-based payment arrangement
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share (in shares)	1	33
Performance shares
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share (in shares)	447	332

Business Combinations - Additio

Business Combinations - Additional Information (Details) $ in Thousands, shares in Millions	3 Months Ended
	Mar. 31, 2021USD ($)clientListshares	Mar. 31, 2020USD ($)clientListshares	Dec. 31, 2020USD ($)
Business Acquisition, Contingent Consideration [Line Items]
Consideration paid in cash	$ 1,900	$ 9,400
Contingent consideration	1,600	4,800
Contingent consideration arrangements - High	1,700	6,200
Aggregate fair value of contingent consideration	1,600	4,700
Contingent consideration, current	22,767		$ 20,288
Contingent consideration, non-current	31,463		$ 34,103
Annual revenue	3,600	6,100
Consideration paid in common stock		900
Goodwill	1,500	11,200
Business combination contingent consideration liability other adjustments based on projected future results of acquisition	700	(700)
Consideration paid in cash	$ 1,500	$ 2,400
Number of common stock issued (in shares) | shares	0.1	0.1
Contingent Purchase Price Liability – Current
Business Acquisition, Contingent Consideration [Line Items]
Contingent consideration, current	$ 600	$ 2,000
Contingent Purchase Price Liability – Non-current
Business Acquisition, Contingent Consideration [Line Items]
Contingent consideration, non-current	1,000	2,700
Acquisition of Client Lists
Business Acquisition, Contingent Consideration [Line Items]
Consideration paid in cash	200	500
Contingent consideration	$ 100	$ 300
Acquisition of Client Lists | Benefits and Insurance Services Practice Group
Business Acquisition, Contingent Consideration [Line Items]
Number of client list purchased | clientList	1	2
Previous Client List Purchases
Business Acquisition, Contingent Consideration [Line Items]
Consideration paid in cash	$ 100	$ 300

Segment Disclosures - Additiona

Segment Disclosures - Additional Information (Details)	3 Months Ended
	Mar. 31, 2021practiceGroup
Segment Reporting [Abstract]
Number of business units of the company	3

Segment Disclosures - Summary o

Segment Disclosures - Summary of Disaggregation of Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 300,730	$ 277,455
Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	204,149	188,777
Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	87,239	79,612
National Practices
Disaggregation of Revenue [Line Items]
Total revenue	9,342	9,066
Accounting, tax, advisory and consulting
Disaggregation of Revenue [Line Items]
Total revenue	204,149	188,777
Accounting, tax, advisory and consulting | Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	204,149	188,777
Accounting, tax, advisory and consulting | Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Accounting, tax, advisory and consulting | National Practices
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Core benefits and insurance services
Disaggregation of Revenue [Line Items]
Total revenue	84,070	76,472
Core benefits and insurance services | Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Core benefits and insurance services | Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	84,070	76,472
Core benefits and insurance services | National Practices
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Non-core benefits and insurance services
Disaggregation of Revenue [Line Items]
Total revenue	3,169	3,140
Non-core benefits and insurance services | Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Non-core benefits and insurance services | Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	3,169	3,140
Non-core benefits and insurance services | National Practices
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Managed networking, hardware services
Disaggregation of Revenue [Line Items]
Total revenue	6,895	6,575
Managed networking, hardware services | Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Managed networking, hardware services | Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	0	0
Managed networking, hardware services | National Practices
Disaggregation of Revenue [Line Items]
Total revenue	6,895	6,575
National practices consulting
Disaggregation of Revenue [Line Items]
Total revenue	2,447	2,491
National practices consulting | Financial Services
Disaggregation of Revenue [Line Items]
Total revenue	0	0
National practices consulting | Benefits & Insurance
Disaggregation of Revenue [Line Items]
Total revenue	0	0
National practices consulting | National Practices
Disaggregation of Revenue [Line Items]
Total revenue	$ 2,447	$ 2,491

Segment Disclosures - Summary_2

Segment Disclosures - Summary of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Revenue	$ 300,730	$ 277,455
Operating expenses	223,971	199,827
Gross margin	76,759	77,628
Corporate general and administrative expenses	14,483	10,489
Operating income	62,276	67,139
Other income (expense):
Interest expense	(877)	(1,119)
Gain on sale of operations, net	0	95
Other income (expense), net	4,789	(15,800)
Total other income (expense), net	3,912	(16,824)
Income from continuing operations before income tax    expense	66,188	50,315
Financial Services
Segment Reporting Information [Line Items]
Revenue	204,149	188,777
Benefits & Insurance
Segment Reporting Information [Line Items]
Revenue	87,239	79,612
National Practices
Segment Reporting Information [Line Items]
Revenue	9,342	9,066
Operating segments | Financial Services
Segment Reporting Information [Line Items]
Revenue	204,149	188,777
Operating expenses	141,746	138,598
Gross margin	62,403	50,179
Corporate general and administrative expenses	0	0
Operating income	62,403	50,179
Other income (expense):
Interest expense	0	0
Gain on sale of operations, net		40
Other income (expense), net	98	19
Total other income (expense), net	98	59
Income from continuing operations before income tax    expense	62,501	50,238
Operating segments | Benefits & Insurance
Segment Reporting Information [Line Items]
Revenue	87,239	79,612
Operating expenses	66,933	65,223
Gross margin	20,306	14,389
Corporate general and administrative expenses	0	0
Operating income	20,306	14,389
Other income (expense):
Interest expense	0	(11)
Gain on sale of operations, net		55
Other income (expense), net	174	96
Total other income (expense), net	174	140
Income from continuing operations before income tax    expense	20,480	14,529
Operating segments | National Practices
Segment Reporting Information [Line Items]
Revenue	9,342	9,066
Operating expenses	8,541	8,283
Gross margin	801	783
Corporate general and administrative expenses	0	0
Operating income	801	783
Other income (expense):
Interest expense	0	0
Gain on sale of operations, net		0
Other income (expense), net	0	1
Total other income (expense), net	0	1
Income from continuing operations before income tax    expense	801	784
Corporate and Other
Segment Reporting Information [Line Items]
Revenue	0	0
Operating expenses	6,751	(12,277)
Gross margin	(6,751)	12,277
Corporate general and administrative expenses	14,483	10,489
Operating income	(21,234)	1,788
Other income (expense):
Interest expense	(877)	(1,108)
Gain on sale of operations, net		0
Other income (expense), net	4,517	(15,916)
Total other income (expense), net	3,640	(17,024)
Income from continuing operations before income tax    expense	$ (17,594)	$ (15,236)

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands, shares in Millions	Apr. 29, 2021	Apr. 01, 2021	Apr. 27, 2021	Mar. 31, 2021	Mar. 31, 2020
Subsequent Event [Line Items]
Share repurchases, value				$ 34,142	$ 29,487
Subsequent Event
Subsequent Event [Line Items]
Share repurchases (in shares)			0.3
Share repurchases, value			$ 9,000
Subsequent Event | BP
Subsequent Event [Line Items]
Business acquisition, estimated annualized revenue	$ 26,000
Subsequent Event | Wright
Subsequent Event [Line Items]
Asset acquisition, estimated annualized revenue		$ 1,200

Uncategorized Items - cbz-20210

Label	Element	Value
Cash Equivalents Included In Funds Held For Clients	cbz_CashEquivalentsIncludedInFundsHeldForClients	$ 94,116,000
Cash Equivalents Included In Funds Held For Clients	cbz_CashEquivalentsIncludedInFundsHeldForClients	118,381,000
Restricted Cash	us-gaap_RestrictedCash	27,618,000
Restricted Cash	us-gaap_RestrictedCash	$ 28,927,000