Barrett Business Services (BBSI) 10-Q 6 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 22, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	BBSI
Entity Registrant Name	BARRETT BUSINESS SERVICES INC
Entity Central Index Key	0000902791
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Current Reporting Status	Yes
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		7,537,056
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, Par Value $0.01 Per Share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	MD
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	0-21886
Entity Tax Identification Number	52-0812977
Entity Address, Address Line One	8100 NE Parkway Drive
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Vancouver
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98662
City Area Code	360
Local Phone Number	828-0700

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 14,272	$ 44,570
Investments	79,373	82,590
Trade accounts receivable, net	165,790	163,561
Income taxes receivable	2,437	1,335
Prepaid expenses and other	16,511	14,919
Restricted cash and investments	120,054	116,873
Total current assets	398,437	423,848
Property, equipment and software, net	34,163	31,724
Operating lease right-of-use assets	25,730	23,805
Restricted cash and investments	346,623	327,326
Goodwill	47,820	47,820
Other assets	3,489	3,618
Deferred income taxes	3,325	2,788
Total assets	859,587	860,929
Current liabilities:
Current portion of long-term debt	221	221
Accounts payable	4,333	5,993
Accrued payroll, payroll taxes and related benefits	180,526	174,168
Current operating lease liabilities	7,046	6,671
Other accrued liabilities	7,043	8,846
Workers' compensation claims liabilities	117,894	118,273
Safety incentives liability	26,330	27,950
Total current liabilities	343,393	342,122
Long-term workers' compensation claims liabilities	327,416	320,713
Long-term debt	3,675	3,730
Long-term operating lease liabilities	19,485	17,883
Customer deposits and other long-term liabilities	4,342	4,682
Total liabilities	698,311	689,130
Commitments and contingencies (Notes 4 and 6)
Stockholders' equity:
Common stock, $.01 par value; 20,500 shares authorized, 7,505 and 7,514 shares issued and outstanding	75	75
Additional paid-in capital	20,925	20,227
Accumulated other comprehensive income	84	2,819
Retained earnings	140,192	148,678
Total stockholders' equity	161,276	171,799
Total liabilities and stockholders' equity	$ 859,587	$ 860,929

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	20,500,000	20,500,000
Common stock, shares issued	7,505,000	7,514,000
Common stock, shares outstanding	7,505,000	7,514,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues:
Total revenues	$ 219,104	$ 218,215
Cost of revenues:
Total cost of revenues	193,053	189,868
Gross margin	26,051	28,347
Selling, general and administrative expenses	32,115	33,160
Depreciation and amortization	1,000	969
Loss from operations	(7,064)	(5,782)
Other income (expense):
Investment income, net	2,967	3,072
Interest expense	(235)	(477)
Other, net	1	12
Other income, net	2,733	2,607
Loss before income taxes	(4,331)	(3,175)
Benefit from income taxes	(924)	(875)
Net loss	$ (3,407)	$ (2,300)
Basic loss per common share	$ (450)	$ (310)
Weighted average number of basic common shares outstanding	7,521	7,407
Diluted loss per common share	$ (450)	$ (310)
Weighted average number of diluted common shares outstanding	7,521	7,407
Professional Employer Service Fees [Member]
Revenues:
Total revenues	$ 193,592	$ 190,527
Staffing Services [Member]
Revenues:
Total revenues	25,512	27,688
Direct Payroll Costs [Member]
Cost of revenues:
Total cost of revenues	19,077	20,842
Payroll Taxes and Benefits [Member]
Cost of revenues:
Total cost of revenues	119,462	114,797
Workers' Compensation [Member]
Cost of revenues:
Total cost of revenues	$ 54,514	$ 54,229

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (3,407)	$ (2,300)
Unrealized (losses) gains on investments, net of tax	(2,735)	3,657
Comprehensive (loss) income	$ (6,142)	$ 1,357

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive (Loss) Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Unrealized (losses) gains on investments, tax	$ (1,046)	$ 1,397

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Retained Earnings [Member]
Beginning Balance at Dec. 31, 2018	$ 119,037	$ 74	$ 15,437	$ (5,068)	$ 108,594
Beginning Balance, shares at Dec. 31, 2018		7,395
Common stock issued on exercise of options, purchase of ESPP shares and vesting of restricted stock units and performance awards	122		122
Common stock issued on exercise of options, purchase of ESPP shares and vesting of restricted stock units and performance awards, shares		17
Common stock repurchased on vesting of restricted stock units and performance awards	(178)		(178)
Common stock repurchased on vesting of restricted stock units and performance awards, shares		(2)
Share-based compensation expense	1,387		1,387
Cash dividends on common stock	(1,852)				(1,852)
Unrealized gain (loss) on investments, net of tax	3,657			3,657
Net loss	(2,300)				(2,300)
Ending Balance at Mar. 31, 2019	119,873	$ 74	16,768	(1,411)	104,442
Ending Balance, shares at Mar. 31, 2019		7,410
Beginning Balance at Dec. 31, 2019	171,799	$ 75	20,227	2,819	148,678
Beginning Balance, shares at Dec. 31, 2019		7,514
Common stock issued on exercise of options, purchase of ESPP shares and vesting of restricted stock units and performance awards	904	$ 1	903
Common stock issued on exercise of options, purchase of ESPP shares and vesting of restricted stock units and performance awards, shares		56
Common stock repurchased on vesting of restricted stock units and performance awards	(378)		(378)
Common stock repurchased on vesting of restricted stock units and performance awards, shares		(6)
Share-based compensation expense	342		342
Company repurchase of common stock	(2,987)	$ (1)	(169)		(2,817)
Company repurchase of common stock, shares		(59)
Cash dividends on common stock	(2,262)				(2,262)
Unrealized gain (loss) on investments, net of tax	(2,735)			(2,735)
Net loss	(3,407)				(3,407)
Ending Balance at Mar. 31, 2020	$ 161,276	$ 75	$ 20,925	$ 84	$ 140,192
Ending Balance, shares at Mar. 31, 2020		7,505

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Stockholders Equity [Abstract]
Cash dividends on common stock per share	$ 0.30	$ 0.25

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net loss	$ (3,407)	$ (2,300)
Reconciliations of net loss to net cash provided by operating activities:
Depreciation and amortization	1,000	969
Non-cash lease expense	1,724	1,773
Investment (accretion) amortization and (gains) losses recognized	81	(130)
Deferred Income taxes	508
Share-based compensation	342	1,387
Changes in certain operating assets and liabilities:
Trade accounts receivable	(2,229)	(2,560)
Income taxes	(1,102)	(843)
Prepaid expenses and other	(1,592)	(2,752)
Accounts payable	(1,660)	1,021
Accrued payroll, payroll taxes and related benefits	6,406	30,647
Other accrued liabilities	(2,095)	(3,512)
Workers' compensation claims liabilities	6,452	9,508
Safety incentives liability	(1,620)	(2,282)
Operating lease liabilities	(1,672)	(1,374)
Other assets and liabilities, net	(95)	1,220
Net cash provided by operating activities	1,041	30,772
Cash flows from investing activities:
Purchase of property, equipment and software	(3,439)	(1,798)
Purchase of investments	(23,722)	(8)
Proceeds from sales and maturities of investments	21,758	15
Purchase of restricted investments	(1,828)	(2,023)
Proceeds from sales and maturities of restricted investments	14,449	30,859
Net cash provided by investing activities	7,218	27,045
Cash flows from financing activities:
Payments on long-term debt	(55)	(55)
Repurchase of common stock	(2,987)
Common stock repurchased on vesting of stock awards	(378)	(178)
Dividends paid	(2,262)	(1,852)
Proceeds from exercise of stock options	904	122
Net cash used in financing activities	(4,778)	(1,963)
Net increase in cash, cash equivalents and restricted cash	3,481	55,854
Cash, cash equivalents and restricted cash, beginning of period	273,341	140,702
Cash, cash equivalents and restricted cash, end of period	$ 276,822	$ 196,556

Basis of Presentation of Interi

Basis of Presentation of Interim Period Statements	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation of Interim Period Statements	Note 1 - Basis of Presentation of Interim Period Statements The accompanying condensed consolidated financial statements are unaudited and have been prepared by Barrett Business Services, Inc. (“BBSI”, the “Company”, “our” or “we”), pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and note disclosures typically included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, the condensed consolidated financial statements include all adjustments, consisting only of normal recurring adjustments, necessary for a fair statement of the results for the interim periods presented. The accompanying condensed financial statements are prepared on a consolidated basis. All intercompany account balances and transactions have been eliminated in consolidation. The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results may differ from such estimates and assumptions. The condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s 2019 Annual Report on Form 10-K at pages 32 – 58. The results of operations for an interim period are not necessarily indicative of the results of operations for a full year. Revenue recognition Professional employer (“PEO”) services are normally used by organizations to satisfy ongoing needs related to the management of human capital and are governed by the terms of a client services agreement which covers all employees at a particular work site. Staffing revenues relate primarily to short-term staffing, contract staffing and on-site management services. The Company’s performance obligations for PEO and staffing services are satisfied, and the related revenue is recognized, as services are rendered by our workforce. Our PEO client service agreements have a minimum term of one year, are renewable on an annual basis, and typically require 30 days’ written notice to cancel or terminate the contract by either party. In addition, our client service agreements provide for immediate termination upon any default of the client regardless of when notice is given. PEO customers are invoiced following the end of each payroll processing cycle, with payment generally due on the invoice date. Staffing customers are invoiced weekly based on agreed rates per employee and actual hours worked, typically with payment terms of 30 days. The amount of earned but unbilled revenue is classified as a receivable on the condensed consolidated balance sheets. We report PEO revenues net of direct payroll costs because we are not the primary obligor for these payments to our clients’ employees. Direct payroll costs include salaries, wages, health insurance, and employee out-of-pocket expenses incurred incidental to employment. We also present revenue net of safety incentives because these incentives represent consideration payable to customers. Cost of revenues Our cost of revenues for PEO services includes employer payroll-related taxes and workers’ compensation costs. Our cost of revenues for staffing services includes direct payroll costs, employer payroll-related taxes, employee benefits, and workers’ compensation costs. Direct payroll costs represent the gross payroll earned by staffing services employees based on salary or hourly wages. Payroll taxes and employee benefits consist of the employer’s portion of Social Security and Medicare taxes, federal and state unemployment taxes, and staffing services employee reimbursements for materials, supplies and other expenses, which are paid by our customer. Workers’ compensation costs consist primarily of claims reserves, claims administration fees, legal fees, medical cost containment (“MCC”) expense, state administrative agency fees, third-party broker commissions, risk manager payroll, premiums for excess insurance, and the fronted insurance program, as well as costs associated with operating our two wholly owned insurance companies, Associated Insurance Company for Excess (“AICE”) and Ecole Insurance Company (“Ecole”). Cash and cash equivalents We consider non-restricted short-term investments that are highly liquid, readily convertible into cash, and have maturities at acquisition of less than three months, to be cash equivalents for purposes of the condensed consolidated statements of cash flows and condensed consolidated balance sheets. The Company maintains cash balances in bank accounts that normally exceed FDIC insured limits. The Company has not experienced any losses related to its cash concentration. Investments The Company classifies investments as available-for-sale. The Company’s investments are reported at fair value with unrealized gains and losses, net of taxes, shown as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Investments are recorded as current on the condensed consolidated balance sheets as the invested funds are available for current operations. Management considers available evidence in evaluating potential impairment of investments, including the extent to which fair value is less than cost and adverse conditions related to the security. In the event of a credit loss, an allowance would be recognized to the extent that the fair value of the security is less than the present value of the expected future cash flows. Realized gains and losses on sales of investments are included in investment income in our condensed consolidated statements of operations. Restricted cash and investments The Company holds restricted cash and investments primarily for the future payment of workers’ compensation claims. These investments are categorized as available-for-sale. They are reported at fair value with unrealized gains and losses, net of taxes, shown as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Restricted cash and investments are classified as current and noncurrent on the condensed consolidated balance sheets based on the nature of the restriction. Management considers available evidence in evaluating potential impairment of restricted investments, including the extent to which fair value is less than cost and adverse conditions related to the security. In the event of a credit loss, an allowance would be recognized to the extent that the fair value of the security is less than the present value of the expected future cash flows. Realized gains and losses on sales of restricted investments are included in investment income in our condensed consolidated statements of operations. Restricted cash and investments also includes investments held as part of the Company’s deferred compensation plan. These investments are classified as trading securities and are recorded at fair value with unrealized gains and losses reported as a component of income (loss) from operations. Allowance for doubtful accounts The Company had an allowance for doubtful accounts of $835,000 and $888,000 at March 31, 2020 and December 31, 2019, respectively. We make estimates of the collectability of our accounts receivable for services provided to our customers based on future expected credit losses. Management analyzes historical bad debts, customer concentrations, customer credit-worthiness, current economic trends and changes in customers’ payment trends when evaluating the adequacy of the allowance for doubtful accounts. If the financial condition of our customers deteriorates, resulting in an impairment of their ability to make payments, additional allowances may be required. Workers’ compensation claims liabilities Our workers’ compensation claims liabilities do not represent an exact calculation of liability but rather management’s best estimate, utilizing actuarial expertise and projection techniques, at a given reporting date. The estimated liability for open workers’ compensation claims is based on an evaluation of information provided by our third-party administrator for workers’ compensation claims, coupled with an actuarial estimate of future loss development with respect to reported claims and incurred but not reported claims (together, “IBNR”). Workers’ compensation claims liabilities include case reserve estimates for reported losses, plus additional amounts for estimated IBNR claims, MCC and legal costs, unallocated loss adjustment expenses and estimated future recoveries. The estimate of incurred costs expected to be paid within one year is included in current liabilities, while the estimate of incurred costs expected to be paid beyond one year is included in long-term liabilities on our condensed consolidated balance sheets. These estimates are reviewed at least quarterly and adjustments to estimated liabilities are reflected in current operating results as they become known. The process of arriving at an estimate of unpaid claims and claims adjustment expense involves a high degree of judgment and is affected by both internal and external events, including changes in claims handling practices, changes in reserve estimation procedures, inflation, trends in the litigation and settlement of pending claims, and legislative changes. Our estimates are based on informed judgment, derived from individual experience and expertise applied to multiple sets of data and analyses. We consider significant facts and circumstances known both at the time that loss reserves are initially established and as new facts and circumstances become known. Due to the inherent uncertainty underlying loss reserve estimates, the expenses incurred through final resolution of our liability for our workers’ compensation claims will likely vary from the related loss reserves at the reporting date. Therefore, as specific claims are paid out in the future, actual paid losses may be materially different from our current loss reserves. A basic premise in most actuarial analyses is that historical data and past patterns demonstrated in the incurred and paid historical data form a reasonable basis upon which to project future outcomes, absent a material change. Significant structural changes to the available data can materially impact the reserve estimation process. To the extent a material change affecting the ultimate claim liability becomes known, such change is quantified to the extent possible through an analysis of internal Company data and, if available and when appropriate, external data. Nonetheless, actuaries exercise a considerable degree of judgment in the evaluation of these factors and the need for such actuarial judgment is more pronounced when faced with material uncertainties. Safety incentives We accrue for and present expected safety incentives as a reduction of revenue. Customer deposits We require deposits from certain PEO customers to cover a portion of our accounts receivable due from such customers in the event of default of payment. Comprehensive income (loss) Comprehensive income (loss) includes all changes in equity during a period except those that resulted from investments by or distributions to the Company’s stockholders. Other comprehensive income (loss) refers to revenues, expenses, gains and losses that under U.S. generally accepted accounting principles (“GAAP”) are included in comprehensive income (loss), but excluded from net income (loss) as these amounts are recorded directly as an adjustment to stockholders’ equity. Our other comprehensive income (loss) comprises unrealized holding gains and losses on our available-for-sale investments. Statements of cash flows Interest paid during the three months ended March 31, 2020 and 2019 did not materially differ from interest expense. No income taxes were paid during the three months ended March 31, 2020 and 2019. Bank deposits and other cash equivalents that are restricted for use are classified as restricted cash. The table below reconciles the cash, cash equivalents and restricted cash balances from our condensed consolidated balance sheets to the amounts reported on the condensed consolidated statements of cash flows (in thousands): March 31, December 31, March 31, December 31, 2020 2019 2019 2018 Cash and cash equivalents $ 14,272 $ 44,570 $ 38,223 $ 35,371 Restricted cash, included in restricted cash and investments 262,550 228,771 158,333 105,331 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 276,822 $ 273,341 $ 196,556 $ 140,702 Basic and diluted earnings per share Basic earnings per share are computed based on the weighted average number of common shares outstanding for each year using the treasury method. Diluted earnings per share reflect the potential effects of the exercise of outstanding stock options and the issuance of stock associated with outstanding restricted stock units. Basic and diluted shares outstanding are summarized as follows (in thousands): Three Months Ended March 31, 2020 2019 Weighted average number of basic shares outstanding 7,521 7,407 Effect of dilutive securities — — Weighted average number of diluted shares outstanding 7,521 7,407 As a result of the net loss for the three months ended March 31, 2020 and 2019, 187,745 and 250,050 potential common shares have been excluded from the calculation of diluted loss per share because their effect would be anti-dilutive. Accounting estimates The preparation of our condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Estimates are used for fair value measurement of investments, allowance for doubtful accounts, deferred income taxes, carrying values for goodwill and property, equipment and software, accrued workers’ compensation liabilities and safety incentive liabilities. Actual results may or may not differ from such estimates. Recent accounting pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, “Financial Instruments – Credit Losses.” The ASU requires the use of an impairment model that is based on expected credit losses rather than incurred losses. The ASU also made changes to the impairment model for available-for-sale securities and requires the use of an allowance approach rather than writing down the security’s cost. The amendments in this update were adopted January 1, 2020 and did not have a material impact on the Company’s financial statements.

Fair Value Measurement

Fair Value Measurement	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurement	Note 2 - Fair Value Measurement The following table summarizes the Company’s investments at March 31, 2020 and December 31, 2019 measured at fair value on a recurring basis (in thousands): March 31, 2020 December 31, 2019 Gross Gross Unrealized Unrealized Gains Recorded Gains Recorded Cost (Losses) Basis Cost (Losses) Basis Current: Cash equivalents: Money market funds $ 2,135 $ — $ 2,135 $ 35,526 $ — $ 35,526 Total cash equivalents 2,135 — 2,135 35,526 — 35,526 Investments: Corporate bonds 36,937 (783 ) 36,154 53,493 156 53,649 Asset backed securities 36,989 (4,434 ) 32,555 14,017 (13 ) 14,004 U.S. government agency securities 7,405 424 7,829 7,408 282 7,690 U.S. treasuries 2,448 17 2,465 4,500 9 4,509 Mortgage backed securities 361 9 370 2,737 1 2,738 Total investments 84,140 (4,767 ) 79,373 82,155 435 82,590 Restricted cash and investments (1) Corporate bonds 99,452 1,629 101,081 98,481 1,931 100,412 Mortgage backed securities 59,961 1,978 61,939 62,930 837 63,767 Money market funds 34,418 (23 ) 34,395 29,046 — 29,046 U.S. government agency securities 25,739 1,166 26,905 27,885 642 28,527 U.S. treasuries 7,271 63 7,334 16,906 21 16,927 Supranational bonds 4,771 71 4,842 4,770 30 4,800 Mutual funds 3,514 — 3,514 3,466 — 3,466 Asset backed securities 291 (2 ) 289 303 — 303 Total restricted cash and investments 235,417 4,882 240,299 243,787 3,461 247,248 Total investments $ 321,692 $ 115 $ 321,807 $ 361,468 $ 3,896 $ 365,364 (1) Included in restricted cash and investments within the condensed consolidated balance sheet is restricted cash of $226.4 million and $197.0 million as of March 31, 2020 and December 31, 2019, respectively, which is excluded from the table above. Restricted cash and investments are classified as current and noncurrent on the balance sheet based on the nature of the restriction. The following table summarizes the Company’s investments at March 31, 2020 and December 31, 2019 measured at fair value on a recurring basis by fair value hierarchy level (in thousands): March 31, 2020 December 31, 2019 Total Total Recorded Recorded Basis Level 1 Level 2 Level 3 Other (1) Basis Level 1 Level 2 Level 3 Other (1) Cash equivalents: Money market funds $ 2,135 $ — $ — $ — $ 2,135 $ 35,526 $ — $ — $ — $ 35,526 Investments: Corporate bonds 36,154 — 36,154 — — 53,649 — 53,649 — — Asset backed securities 32,555 — 32,555 — — 14,004 — 14,004 — — U.S. government agency securities 7,829 — 7,829 — — 7,690 — 7,690 — — U.S. treasuries 2,465 — 2,465 — — 4,509 — 4,509 — — Mortgage backed securities 370 — 370 — — 2,738 — 2,738 — — Restricted cash and investments: Corporate bonds 101,081 — 101,081 — — 100,412 — 100,412 — — Mortgage backed securities 61,939 — 61,939 — — 63,767 — 63,767 — — Money market funds 34,395 — — — 34,395 29,046 — — — 29,046 U.S. government agency securities 26,905 — 26,905 — — 28,527 — 28,527 — — U.S. treasuries 7,334 — 7,334 — — 16,927 — 16,927 — — Supranational bonds 4,842 — 4,842 — — 4,800 — 4,800 — — Mutual funds 3,514 3,514 — — 3,466 3,466 — — Asset backed securities 289 — 289 — — 303 — 303 — — Total investments $ 321,807 $ 3,514 $ 281,763 $ — $ 36,530 $ 365,364 $ 3,466 $ 297,326 $ — $ 64,572 (1) Investments in money market funds measured at fair value using the net asset value per share practical expedient are not subject to hierarchy level classification disclosure. The Company invests in money market funds that seek to maintain a stable net asset value. These investments include commingled funds that comprise high-quality short-term securities representing liquid debt and monetary instruments where the redemption value is likely to be the fair value. Redemption is permitted daily without written notice. The following table summarizes the contractual maturities of the Company’s available-for-sale securities at March 31, 2020. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties. March 31, 2020 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 16,277 $ 81,828 $ 25,001 $ 14,129 $ 137,235 Money market funds 36,530 — — — 36,530 U.S. government agency securities — 6,505 28,229 — 34,734 Asset backed securities — 303 — 32,541 32,844 U.S. treasuries 8,569 1,230 — — 9,799 Supranational bonds 4,842 — — — 4,842 Total $ 66,218 $ 89,866 $ 53,230 $ 46,670 $ 255,984 December 31, 2019 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 7,238 $ 120,887 $ 25,936 $ — $ 154,061 Money market funds 64,572 — — — 64,572 U.S. government agency securities 2,128 6,425 27,664 — 36,217 U.S. treasuries 20,632 804 — — 21,436 Asset backed securities — 319 — 13,988 14,307 Supranational bonds — 4,800 — — 4,800 Total $ 94,570 $ 133,235 $ 53,600 $ 13,988 $ 295,393 The average contractual maturity of mortgage backed securities was 17 years as of March 31, 2020 and December 31, 2019, which are excluded from the tables above.

Workers' Compensation Claims

Workers' Compensation Claims	3 Months Ended
	Mar. 31, 2020
Text Block [Abstract]
Workers' Compensation Claims	Note 3 – Workers’ Compensation Claims The following table summarizes the aggregate workers’ compensation reserve activity (in thousands): Three Months Ended March 31, 2020 2019 Beginning balance Workers' compensation claims liabilities $ 438,986 $ 413,397 Add: claims expense accrual Current period 38,492 40,385 Prior periods (813 ) (1,700 ) 37,679 38,685 Less: claim payments related to Current period 1,550 1,459 Prior periods 29,677 27,716 31,227 29,175 Change in claims incurred in excess of retention limits (128 ) (35 ) Ending balance Workers' compensation claims liabilities $ 445,310 $ 422,872 Incurred but not reported (IBNR) $ 282,497 $ 268,291 Ratio of IBNR to workers' compensation claims liabilities 63 % 63 % The Company is a self-insured employer with respect to workers' compensation coverage for all of its employees (including employees co-employed through our client service agreements) working in Colorado, Maryland and Oregon. In the state of Washington, state law allows only the Company's staffing services and internal management employees to be covered under the Company's self-insured workers' compensation program. The Company also operates a wholly owned, fully licensed insurance company, Ecole, which provides workers’ compensation coverage to the Company’s employees working in Arizona and Utah. For all other clients, the Company obtains policies from Chubb Limited (“Chubb”) through an arrangement known as a fronted program, which provides a licensed, admitted insurance carrier to issue policies on behalf of the Company. Chubb assumes credit risk should the Company be unable to satisfy its indemnification obligations. Through various insurance arrangements, the Company retains risk of loss up to the first $5.0 million per occurrence, except in Maryland and Colorado, where our retention per occurrence is $1.0 million and $2.0 million, respectively. The fronted program with Chubb requires that collateral be advanced at the inception of the policy term. To partially satisfy these collateral requirements, the Company provided a surety bond of $15.0 million and a letter of credit of $63.7 million from its principal bank, Wells Fargo Bank, National Association (the “Bank”). In addition, The states of California, Maryland, Oregon, Washington, Colorado and Delaware required us to maintain collateral totaling $76.1 million at March 31, 2020 and December 31, 2019 to cover potential workers’ compensation claims losses related to the Company’s current and former status as a self-insured employer. At March 31, 2020, the Company provided surety bonds and standby letters of credit totaling $76.1 million, including a California requirement of $55.6 million. The Company provided a total of $445.3 million and $439.0 million at March 31, 2020 and December 31, 2019, respectively, as an estimated future liability for unsettled workers' compensation claims liabilities. Of this amount, $3.2 million and $3.3 million at March 31, 2020 and December 31, 2019, respectively, represent case reserves incurred in excess of the Company’s retention. The accrual for costs incurred in excess of retention limits is offset by a receivable from excess insurance carriers of $3.2 million and $3.3 million at March 31, 2020 and December 31, 2019, respectively, included in other assets on the condensed consolidated balance sheets.

Revolving Credit Facility and L

Revolving Credit Facility and Long-Term Debt	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Revolving Credit Facility and Long-Term Debt	Note 4 - Revolving Credit Facility and Long-Term Debt On August 6, 2019, the Company entered into an amended credit agreement (the “Agreement”) with the Bank, which superseded the previous agreement. The Agreement increased the revolving credit line from $28.0 million to $33.0 million and increased the sublimit for standby letters of credit from $7.5 million to $8.0 million. At March 31, 2020, $5.8 million of the sublimit for standby letters of credit was used. The Agreement expires on July 1, 2022. Advances under the revolving credit line bear interest, as selected by the Company, of (a) the daily floating rate of one-month LIBOR plus 1.75% or (b) The Agreement also provides for a $63.7 million standby letter of credit (the “Chubb Letter of Credit”). The Chubb Letter of Credit has an expiration date of July 1, 2020, subject to automatic renewal in specified circumstances. The Bank has been granted a security interest of first priority in certain blocked securities accounts (collectively, the “Collateral Accounts”). The Company has agreed to deposit in the Collateral Accounts 50% of the Company’s consolidated net income (after tax and less cash dividends) for each quarter plus, to the extent necessary, an additional amount by May 15 each year so that the deposits in the Collateral Accounts for the prior year total at least $16 million. Through the first quarter of 2020, the Company deposited $32.4 million into the Collateral Accounts. The initial fee paid under the Chubb Letter of Credit in June 2018 was equal to 2.5% of the face amount thereof. Upon annual renewal, the fees payable to the Bank quarterly in advance include (a) a fee at the annual rate of 2.5%, calculated based on the difference between the face amount of the Chubb Letter of Credit and 95% of the aggregate value of the Collateral Accounts as of the end of the previous quarter, (b) a fee at the annual rate of 1.0% calculated based on the balance of the face amount, and (c) other fees upon the payment or negotiation of each drawing under the Chubb Letter of Credit. The Agreement requires the satisfaction of certain financial covenants as follows: • EBITDA [net income before taxes plus interest expense (net of capitalized interest expense), depreciation expense, and amortization expense] on a rolling four-quarter basis of not less than $30 million at the end of each fiscal quarter; and • ratio of restricted and unrestricted cash and investments to workers’ compensation and safety incentive liabilities of at least 1.0:1.0, measured quarterly. The Agreement includes certain additional restrictions as follows: • incurring additional indebtedness is prohibited without the prior approval of the Bank, other than purchase financing (including capital leases) for the acquisition of assets, provided that the aggregate of all purchase financing does not exceed $1,000,000 at any time; • the Company may not terminate or cancel any of the AICE policies without the Bank’s prior written consent; and • the Company may not redeem, retire, repurchase or otherwise acquire any of its stock in excess of $15 million in any rolling 12-month period without the Bank’s prior written consent. The Agreement also contains customary events of default and specified cross-defaults under the Company’s workers’ compensation insurance arrangements. If an event of default under the Agreement occurs and is continuing, the Bank may declare any outstanding obligations under the Agreement to be immediately due and payable. At March 31, 2020, the Company was in compliance with all covenants. The Company maintains a mortgage loan with the Bank with a balance of approximately $3.9 million and $4.0 million at March 31, 2020 and December 31, 2019, respectively, secured by the Company’s corporate office building in Vancouver, Washington. This loan requires payment of monthly installments of $18,375, bearing interest at the

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 5 – Income Taxes Under ASC 740, “Income Taxes,” management evaluates the realizability of the deferred tax assets on a quarterly basis under a “more-likely than not” standard. As part of this evaluation, management reviews all evidence both positive and negative to determine if a valuation allowance is needed. One component of this analysis is to determine whether the Company was in a cumulative loss position for the most recent 12 quarters. The Company was in a cumulative income position for the 12 quarters ended March 31, 2020. The Company’s realization of a portion of net deferred tax assets is based in part on our estimates of the timing of reversals of certain temporary differences and on the generation of taxable income before such reversals. The Company is subject to income taxes in U.S. federal and multiple state and local tax jurisdictions. The Internal Revenue Service is examining the Company’s federal tax returns for the years ended December 31, 2011, 2012, 2013 and 2014. In the major jurisdictions where it operates, the Company is generally no longer subject to income tax examinations by tax authorities for the 2015 tax year and tax years before 2011. As of March 31, 2020, the Company had no material unrecognized tax benefits. A portion of the consolidated income the Company generates is not subject to state income tax. Depending on the percentage of this income as compared to total consolidated income, the Company's state effective rate could fluctuate from expectations.

Litigation

Litigation	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Litigation	Note 6 – Litigation On November 21, 2012, David Kaanaana (“Kaanaana”), a former staffing employee, filed a California wage and hour violations lawsuit against BBSI. On May 19, 2016, the court entered a ruling in favor of BBSI, which was subsequently appealed by the plaintiffs. On November 30, 2018, the California Court of Appeal for the Second Appellate District returned its decision in Kaanaana v. Barrett Business Services, Inc., overruling the trial court's decision to dismiss plaintiffs' claims and holding that prevailing wage requirements applicable to “public works” apply to certain types of districts. On January 9, 2019, BBSI filed a petition of review to the California Supreme Court. An amicus letter in support of the petition was filed by the Sanitation Districts of Los Angeles County, joined in by numerous other "special districts" in California. On February 27, 2019, the California Supreme Court granted the petition to review the appellate court’s decision. BBSI is subject to other legal proceedings and claims that arise in the ordinary course of our business.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Note 7 – Subsequent Events COVID-19 Pandemic In March 2020, the World Health Organization declared COVID-19 a pandemic and recommended containment and mitigation measures worldwide. On March 13, 2020, President Trump announced a National Emergency relating to the disease. In response to the COVID-19 pandemic, state governments nationwide, including the states where BBSI and our clients operate, have taken preventative actions such as shelter-in-place orders, restrictions on travel, and temporary closures of businesses deemed to be non-essential. The full impact of the COVID-19 pandemic on our full year financial results will depend on future developments, such as the ultimate duration and scope of the outbreak, its impact on our clients, the rate at which economic conditions, operations, and demand for our services return to pre-COVID-19 levels, and the potential for recession in our key markets due to the effects of the pandemic. Accordingly, the ultimate impact on the Company cannot be determined at this time. Nevertheless, despite the uncertainty of the COVID-19 situation, we expect our full year 2020 results to be adversely affected. Revolving Credit Facility In May 2020, the Company reached an agreement, in principal, with Wells Fargo Bank, National Association, to increase the revolving credit line from $33.0 million to $50.0 million and extend the expiration date of the credit facility to July 2021.

Basis of Presentation of Inte_2

Basis of Presentation of Interim Period Statements (Policies)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Revenue recognition	Revenue recognition Professional employer (“PEO”) services are normally used by organizations to satisfy ongoing needs related to the management of human capital and are governed by the terms of a client services agreement which covers all employees at a particular work site. Staffing revenues relate primarily to short-term staffing, contract staffing and on-site management services. The Company’s performance obligations for PEO and staffing services are satisfied, and the related revenue is recognized, as services are rendered by our workforce. Our PEO client service agreements have a minimum term of one year, are renewable on an annual basis, and typically require 30 days’ written notice to cancel or terminate the contract by either party. In addition, our client service agreements provide for immediate termination upon any default of the client regardless of when notice is given. PEO customers are invoiced following the end of each payroll processing cycle, with payment generally due on the invoice date. Staffing customers are invoiced weekly based on agreed rates per employee and actual hours worked, typically with payment terms of 30 days. The amount of earned but unbilled revenue is classified as a receivable on the condensed consolidated balance sheets. We report PEO revenues net of direct payroll costs because we are not the primary obligor for these payments to our clients’ employees. Direct payroll costs include salaries, wages, health insurance, and employee out-of-pocket expenses incurred incidental to employment. We also present revenue net of safety incentives because these incentives represent consideration payable to customers.
Cost of revenues	Cost of revenues Our cost of revenues for PEO services includes employer payroll-related taxes and workers’ compensation costs. Our cost of revenues for staffing services includes direct payroll costs, employer payroll-related taxes, employee benefits, and workers’ compensation costs. Direct payroll costs represent the gross payroll earned by staffing services employees based on salary or hourly wages. Payroll taxes and employee benefits consist of the employer’s portion of Social Security and Medicare taxes, federal and state unemployment taxes, and staffing services employee reimbursements for materials, supplies and other expenses, which are paid by our customer. Workers’ compensation costs consist primarily of claims reserves, claims administration fees, legal fees, medical cost containment (“MCC”) expense, state administrative agency fees, third-party broker commissions, risk manager payroll, premiums for excess insurance, and the fronted insurance program, as well as costs associated with operating our two wholly owned insurance companies, Associated Insurance Company for Excess (“AICE”) and Ecole Insurance Company (“Ecole”).
Cash and cash equivalents	Cash and cash equivalents We consider non-restricted short-term investments that are highly liquid, readily convertible into cash, and have maturities at acquisition of less than three months, to be cash equivalents for purposes of the condensed consolidated statements of cash flows and condensed consolidated balance sheets. The Company maintains cash balances in bank accounts that normally exceed FDIC insured limits. The Company has not experienced any losses related to its cash concentration.
Investments	Investments The Company classifies investments as available-for-sale. The Company’s investments are reported at fair value with unrealized gains and losses, net of taxes, shown as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Investments are recorded as current on the condensed consolidated balance sheets as the invested funds are available for current operations. Management considers available evidence in evaluating potential impairment of investments, including the extent to which fair value is less than cost and adverse conditions related to the security. In the event of a credit loss, an allowance would be recognized to the extent that the fair value of the security is less than the present value of the expected future cash flows. Realized gains and losses on sales of investments are included in investment income in our condensed consolidated statements of operations.
Restricted cash and investments	Restricted cash and investments The Company holds restricted cash and investments primarily for the future payment of workers’ compensation claims. These investments are categorized as available-for-sale. They are reported at fair value with unrealized gains and losses, net of taxes, shown as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Restricted cash and investments are classified as current and noncurrent on the condensed consolidated balance sheets based on the nature of the restriction. Management considers available evidence in evaluating potential impairment of restricted investments, including the extent to which fair value is less than cost and adverse conditions related to the security. In the event of a credit loss, an allowance would be recognized to the extent that the fair value of the security is less than the present value of the expected future cash flows. Realized gains and losses on sales of restricted investments are included in investment income in our condensed consolidated statements of operations. Restricted cash and investments also includes investments held as part of the Company’s deferred compensation plan. These investments are classified as trading securities and are recorded at fair value with unrealized gains and losses reported as a component of income (loss) from operations.
Allowance for doubtful accounts	Allowance for doubtful accounts The Company had an allowance for doubtful accounts of $835,000 and $888,000 at March 31, 2020 and December 31, 2019, respectively. We make estimates of the collectability of our accounts receivable for services provided to our customers based on future expected credit losses. Management analyzes historical bad debts, customer concentrations, customer credit-worthiness, current economic trends and changes in customers’ payment trends when evaluating the adequacy of the allowance for doubtful accounts. If the financial condition of our customers deteriorates, resulting in an impairment of their ability to make payments, additional allowances may be required.
Workers' compensation claims liabilities	Workers’ compensation claims liabilities Our workers’ compensation claims liabilities do not represent an exact calculation of liability but rather management’s best estimate, utilizing actuarial expertise and projection techniques, at a given reporting date. The estimated liability for open workers’ compensation claims is based on an evaluation of information provided by our third-party administrator for workers’ compensation claims, coupled with an actuarial estimate of future loss development with respect to reported claims and incurred but not reported claims (together, “IBNR”). Workers’ compensation claims liabilities include case reserve estimates for reported losses, plus additional amounts for estimated IBNR claims, MCC and legal costs, unallocated loss adjustment expenses and estimated future recoveries. The estimate of incurred costs expected to be paid within one year is included in current liabilities, while the estimate of incurred costs expected to be paid beyond one year is included in long-term liabilities on our condensed consolidated balance sheets. These estimates are reviewed at least quarterly and adjustments to estimated liabilities are reflected in current operating results as they become known. The process of arriving at an estimate of unpaid claims and claims adjustment expense involves a high degree of judgment and is affected by both internal and external events, including changes in claims handling practices, changes in reserve estimation procedures, inflation, trends in the litigation and settlement of pending claims, and legislative changes. Our estimates are based on informed judgment, derived from individual experience and expertise applied to multiple sets of data and analyses. We consider significant facts and circumstances known both at the time that loss reserves are initially established and as new facts and circumstances become known. Due to the inherent uncertainty underlying loss reserve estimates, the expenses incurred through final resolution of our liability for our workers’ compensation claims will likely vary from the related loss reserves at the reporting date. Therefore, as specific claims are paid out in the future, actual paid losses may be materially different from our current loss reserves. A basic premise in most actuarial analyses is that historical data and past patterns demonstrated in the incurred and paid historical data form a reasonable basis upon which to project future outcomes, absent a material change. Significant structural changes to the available data can materially impact the reserve estimation process. To the extent a material change affecting the ultimate claim liability becomes known, such change is quantified to the extent possible through an analysis of internal Company data and, if available and when appropriate, external data. Nonetheless, actuaries exercise a considerable degree of judgment in the evaluation of these factors and the need for such actuarial judgment is more pronounced when faced with material uncertainties.
Safety incentives	Safety incentives We accrue for and present expected safety incentives as a reduction of revenue.
Customer deposits	Customer deposits We require deposits from certain PEO customers to cover a portion of our accounts receivable due from such customers in the event of default of payment.
Comprehensive income (loss)	Comprehensive income (loss) Comprehensive income (loss) includes all changes in equity during a period except those that resulted from investments by or distributions to the Company’s stockholders. Other comprehensive income (loss) refers to revenues, expenses, gains and losses that under U.S. generally accepted accounting principles (“GAAP”) are included in comprehensive income (loss), but excluded from net income (loss) as these amounts are recorded directly as an adjustment to stockholders’ equity. Our other comprehensive income (loss) comprises unrealized holding gains and losses on our available-for-sale investments.
Statements of cash flows	Statements of cash flows Interest paid during the three months ended March 31, 2020 and 2019 did not materially differ from interest expense. No income taxes were paid during the three months ended March 31, 2020 and 2019. Bank deposits and other cash equivalents that are restricted for use are classified as restricted cash. The table below reconciles the cash, cash equivalents and restricted cash balances from our condensed consolidated balance sheets to the amounts reported on the condensed consolidated statements of cash flows (in thousands): March 31, December 31, March 31, December 31, 2020 2019 2019 2018 Cash and cash equivalents $ 14,272 $ 44,570 $ 38,223 $ 35,371 Restricted cash, included in restricted cash and investments 262,550 228,771 158,333 105,331 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 276,822 $ 273,341 $ 196,556 $ 140,702
Basic and diluted earnings per share	Basic and diluted earnings per share Basic earnings per share are computed based on the weighted average number of common shares outstanding for each year using the treasury method. Diluted earnings per share reflect the potential effects of the exercise of outstanding stock options and the issuance of stock associated with outstanding restricted stock units. Basic and diluted shares outstanding are summarized as follows (in thousands): Three Months Ended March 31, 2020 2019 Weighted average number of basic shares outstanding 7,521 7,407 Effect of dilutive securities — — Weighted average number of diluted shares outstanding 7,521 7,407 As a result of the net loss for the three months ended March 31, 2020 and 2019, 187,745 and 250,050 potential common shares have been excluded from the calculation of diluted loss per share because their effect would be anti-dilutive.
Accounting estimates	Accounting estimates The preparation of our condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Estimates are used for fair value measurement of investments, allowance for doubtful accounts, deferred income taxes, carrying values for goodwill and property, equipment and software, accrued workers’ compensation liabilities and safety incentive liabilities. Actual results may or may not differ from such estimates.
Recent accounting pronouncements	Recent accounting pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, “Financial Instruments – Credit Losses.” The ASU requires the use of an impairment model that is based on expected credit losses rather than incurred losses. The ASU also made changes to the impairment model for available-for-sale securities and requires the use of an allowance approach rather than writing down the security’s cost. The amendments in this update were adopted January 1, 2020 and did not have a material impact on the Company’s financial statements.

Basis of Presentation of Inte_3

Basis of Presentation of Interim Period Statements (Tables)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Reconciles of Cash, Cash Equivalents and Restricted Cash Balances	The table below reconciles the cash, cash equivalents and restricted cash balances from our condensed consolidated balance sheets to the amounts reported on the condensed consolidated statements of cash flows (in thousands): March 31, December 31, March 31, December 31, 2020 2019 2019 2018 Cash and cash equivalents $ 14,272 $ 44,570 $ 38,223 $ 35,371 Restricted cash, included in restricted cash and investments 262,550 228,771 158,333 105,331 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 276,822 $ 273,341 $ 196,556 $ 140,702
Summary of Basic and Diluted Common Shares Outstanding	Basic and diluted shares outstanding are summarized as follows (in thousands): Three Months Ended March 31, 2020 2019 Weighted average number of basic shares outstanding 7,521 7,407 Effect of dilutive securities — — Weighted average number of diluted shares outstanding 7,521 7,407

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Summary of Investments Measured at Fair Value on Recurring Basis	The following table summarizes the Company’s investments at March 31, 2020 and December 31, 2019 measured at fair value on a recurring basis (in thousands): March 31, 2020 December 31, 2019 Gross Gross Unrealized Unrealized Gains Recorded Gains Recorded Cost (Losses) Basis Cost (Losses) Basis Current: Cash equivalents: Money market funds $ 2,135 $ — $ 2,135 $ 35,526 $ — $ 35,526 Total cash equivalents 2,135 — 2,135 35,526 — 35,526 Investments: Corporate bonds 36,937 (783 ) 36,154 53,493 156 53,649 Asset backed securities 36,989 (4,434 ) 32,555 14,017 (13 ) 14,004 U.S. government agency securities 7,405 424 7,829 7,408 282 7,690 U.S. treasuries 2,448 17 2,465 4,500 9 4,509 Mortgage backed securities 361 9 370 2,737 1 2,738 Total investments 84,140 (4,767 ) 79,373 82,155 435 82,590 Restricted cash and investments (1) Corporate bonds 99,452 1,629 101,081 98,481 1,931 100,412 Mortgage backed securities 59,961 1,978 61,939 62,930 837 63,767 Money market funds 34,418 (23 ) 34,395 29,046 — 29,046 U.S. government agency securities 25,739 1,166 26,905 27,885 642 28,527 U.S. treasuries 7,271 63 7,334 16,906 21 16,927 Supranational bonds 4,771 71 4,842 4,770 30 4,800 Mutual funds 3,514 — 3,514 3,466 — 3,466 Asset backed securities 291 (2 ) 289 303 — 303 Total restricted cash and investments 235,417 4,882 240,299 243,787 3,461 247,248 Total investments $ 321,692 $ 115 $ 321,807 $ 361,468 $ 3,896 $ 365,364 (1) Included in restricted cash and investments within the condensed consolidated balance sheet is restricted cash of $226.4 million and $197.0 million as of March 31, 2020 and December 31, 2019, respectively, which is excluded from the table above. Restricted cash and investments are classified as current and noncurrent on the balance sheet based on the nature of the restriction.
Summary of Assets Measured at Fair Value on Recurring Basis	The following table summarizes the Company’s investments at March 31, 2020 and December 31, 2019 measured at fair value on a recurring basis by fair value hierarchy level (in thousands): March 31, 2020 December 31, 2019 Total Total Recorded Recorded Basis Level 1 Level 2 Level 3 Other (1) Basis Level 1 Level 2 Level 3 Other (1) Cash equivalents: Money market funds $ 2,135 $ — $ — $ — $ 2,135 $ 35,526 $ — $ — $ — $ 35,526 Investments: Corporate bonds 36,154 — 36,154 — — 53,649 — 53,649 — — Asset backed securities 32,555 — 32,555 — — 14,004 — 14,004 — — U.S. government agency securities 7,829 — 7,829 — — 7,690 — 7,690 — — U.S. treasuries 2,465 — 2,465 — — 4,509 — 4,509 — — Mortgage backed securities 370 — 370 — — 2,738 — 2,738 — — Restricted cash and investments: Corporate bonds 101,081 — 101,081 — — 100,412 — 100,412 — — Mortgage backed securities 61,939 — 61,939 — — 63,767 — 63,767 — — Money market funds 34,395 — — — 34,395 29,046 — — — 29,046 U.S. government agency securities 26,905 — 26,905 — — 28,527 — 28,527 — — U.S. treasuries 7,334 — 7,334 — — 16,927 — 16,927 — — Supranational bonds 4,842 — 4,842 — — 4,800 — 4,800 — — Mutual funds 3,514 3,514 — — 3,466 3,466 — — Asset backed securities 289 — 289 — — 303 — 303 — — Total investments $ 321,807 $ 3,514 $ 281,763 $ — $ 36,530 $ 365,364 $ 3,466 $ 297,326 $ — $ 64,572 (1) Investments in money market funds measured at fair value using the net asset value per share practical expedient are not subject to hierarchy level classification disclosure. The Company invests in money market funds that seek to maintain a stable net asset value. These investments include commingled funds that comprise high-quality short-term securities representing liquid debt and monetary instruments where the redemption value is likely to be the fair value. Redemption is permitted daily without written notice.
Summary of Contractual Maturities of Available for Sale Securities	The following table summarizes the contractual maturities of the Company’s available-for-sale securities at March 31, 2020. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties. March 31, 2020 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 16,277 $ 81,828 $ 25,001 $ 14,129 $ 137,235 Money market funds 36,530 — — — 36,530 U.S. government agency securities — 6,505 28,229 — 34,734 Asset backed securities — 303 — 32,541 32,844 U.S. treasuries 8,569 1,230 — — 9,799 Supranational bonds 4,842 — — — 4,842 Total $ 66,218 $ 89,866 $ 53,230 $ 46,670 $ 255,984 December 31, 2019 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 7,238 $ 120,887 $ 25,936 $ — $ 154,061 Money market funds 64,572 — — — 64,572 U.S. government agency securities 2,128 6,425 27,664 — 36,217 U.S. treasuries 20,632 804 — — 21,436 Asset backed securities — 319 — 13,988 14,307 Supranational bonds — 4,800 — — 4,800 Total $ 94,570 $ 133,235 $ 53,600 $ 13,988 $ 295,393

Workers' Compensation Claims (T

Workers' Compensation Claims (Tables)	3 Months Ended
	Mar. 31, 2020
Text Block [Abstract]
Summarizes Aggregate Workers' Compensation Reserve Activity	The following table summarizes the aggregate workers’ compensation reserve activity (in thousands): Three Months Ended March 31, 2020 2019 Beginning balance Workers' compensation claims liabilities $ 438,986 $ 413,397 Add: claims expense accrual Current period 38,492 40,385 Prior periods (813 ) (1,700 ) 37,679 38,685 Less: claim payments related to Current period 1,550 1,459 Prior periods 29,677 27,716 31,227 29,175 Change in claims incurred in excess of retention limits (128 ) (35 ) Ending balance Workers' compensation claims liabilities $ 445,310 $ 422,872 Incurred but not reported (IBNR) $ 282,497 $ 268,291 Ratio of IBNR to workers' compensation claims liabilities 63 % 63 %

Basis of Presentation of Inte_4

Basis of Presentation of Interim Period Statements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020USD ($)Companyshares	Mar. 31, 2019USD ($)shares	Dec. 31, 2019USD ($)
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Revenue recognition professional employer service contracts term	1 year
Professional employer service contract cancellation and termination period	30 days
Payment term for staffing customers	30 days
Number of wholly-owned insurance companies | Company	2
Cash and cash equivalents, maturity term	3 months
Allowance for doubtful accounts	$ 835,000		$ 888,000
Estimate of liability for unpaid safety incentives	26,300,000		$ 28,000,000
Income taxes paid	$ 0	$ 0
Potential common shares excluded from calculation of diluted loss per share | shares	187,745	250,050

Basis of Presentation of Inte_5

Basis of Presentation of Interim Period Statements - Schedule of Reconciles of Cash, Cash Equivalents and Restricted Cash Balances (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 14,272	$ 44,570	$ 38,223	$ 35,371
Restricted cash, included in restricted cash and investments	262,550	228,771	158,333	105,331
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$ 276,822	$ 273,341	$ 196,556	$ 140,702

Basis of Presentation of Inte_6

Basis of Presentation of Interim Period Statements - Summary of Basic and Diluted Common Shares Outstanding (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Weighted Average Number Of Shares Outstanding Diluted Disclosure Items [Abstract]
Weighted average number of basic shares outstanding	7,521	7,407
Weighted average number of diluted shares outstanding	7,521	7,407

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	$ 321,692	$ 361,468
Gross Unrealized Gains (Losses)	115	3,896
Recorded Basis	321,807	365,364
Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,135	35,526
Recorded Basis	2,135	35,526
Cash and Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,135	35,526
Recorded Basis	2,135	35,526
Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	84,140	82,155
Gross Unrealized Gains (Losses)	(4,767)	435
Recorded Basis	79,373	82,590
Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	36,937	53,493
Gross Unrealized Gains (Losses)	(783)	156
Recorded Basis	36,154	53,649
Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	36,989	14,017
Gross Unrealized Gains (Losses)	(4,434)	(13)
Recorded Basis	32,555	14,004
Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	7,405	7,408
Gross Unrealized Gains (Losses)	424	282
Recorded Basis	7,829	7,690
Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,448	4,500
Gross Unrealized Gains (Losses)	17	9
Recorded Basis	2,465	4,509
Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	361	2,737
Gross Unrealized Gains (Losses)	9	1
Recorded Basis	370	2,738
Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	235,417	243,787
Gross Unrealized Gains (Losses)	4,882	3,461
Recorded Basis	240,299	247,248
Restricted Cash and Investments [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	34,418	29,046
Gross Unrealized Gains (Losses)	(23)
Recorded Basis	34,395	29,046
Restricted Cash and Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	99,452	98,481
Gross Unrealized Gains (Losses)	1,629	1,931
Recorded Basis	101,081	100,412
Restricted Cash and Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	291	303
Gross Unrealized Gains (Losses)	(2)
Recorded Basis	289	303
Restricted Cash and Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	25,739	27,885
Gross Unrealized Gains (Losses)	1,166	642
Recorded Basis	26,905	28,527
Restricted Cash and Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	7,271	16,906
Gross Unrealized Gains (Losses)	63	21
Recorded Basis	7,334	16,927
Restricted Cash and Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	59,961	62,930
Gross Unrealized Gains (Losses)	1,978	837
Recorded Basis	61,939	63,767
Restricted Cash and Investments [Member] | Supranational Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	4,771	4,770
Gross Unrealized Gains (Losses)	71	30
Recorded Basis	4,842	4,800
Restricted Cash and Investments [Member] | Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	3,514	3,466
Recorded Basis	$ 3,514	$ 3,466

Fair Value Measurement - Summ_2

Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Restricted cash	$ 226.4	$ 197

Fair Value Measurement - Summ_3

Fair Value Measurement - Summary of Assets Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	$ 321,807	$ 365,364
Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	36,530	64,572
Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	3,514	3,466
Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	281,763	297,326
Cash and Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,135	35,526
Cash and Cash Equivalents [Member] | Money Market Funds [Member] | Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,135	35,526
Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	36,154	53,649
Investments [Member] | Corporate Bonds [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	36,154	53,649
Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	370	2,738
Investments [Member] | Mortgage Backed Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	370	2,738
Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,465	4,509
Investments [Member] | U.S. Treasuries [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,465	4,509
Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	7,829	7,690
Investments [Member] | U.S. Government Agency Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	7,829	7,690
Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	32,555	14,004
Investments [Member] | Asset Backed Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	32,555	14,004
Restricted Cash and Investments [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	34,395	29,046
Restricted Cash and Investments [Member] | Money Market Funds [Member] | Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	34,395	29,046
Restricted Cash and Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	101,081	100,412
Restricted Cash and Investments [Member] | Corporate Bonds [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	101,081	100,412
Restricted Cash and Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	61,939	63,767
Restricted Cash and Investments [Member] | Mortgage Backed Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	61,939	63,767
Restricted Cash and Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	7,334	16,927
Restricted Cash and Investments [Member] | U.S. Treasuries [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	7,334	16,927
Restricted Cash and Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	26,905	28,527
Restricted Cash and Investments [Member] | U.S. Government Agency Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	26,905	28,527
Restricted Cash and Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	289	303
Restricted Cash and Investments [Member] | Asset Backed Securities [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	289	303
Restricted Cash and Investments [Member] | Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	3,514	3,466
Restricted Cash and Investments [Member] | Mutual Funds [Member] | Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	3,514	3,466
Restricted Cash and Investments [Member] | Supranational Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	4,842	4,800
Restricted Cash and Investments [Member] | Supranational Bonds [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	$ 4,842	$ 4,800

Fair Value Measurement - Summ_4

Fair Value Measurement - Summary of Contractual Maturities of Available for Sale Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	$ 66,218	$ 94,570
Available for sale securities, contractual maturities between 1 to 5 years	89,866	133,235
Available for sale securities, contractual maturities between 5 to 10 years	53,230	53,600
Available for sale securities, contractual maturities after 10 years	46,670	13,988
Available for sale securities, contractual maturities, Total	255,984	295,393
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	16,277	7,238
Available for sale securities, contractual maturities between 1 to 5 years	81,828	120,887
Available for sale securities, contractual maturities between 5 to 10 years	25,001	25,936
Available for sale securities, contractual maturities after 10 years	14,129
Available for sale securities, contractual maturities, Total	137,235	154,061
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	36,530	64,572
Available for sale securities, contractual maturities, Total	36,530	64,572
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year		2,128
Available for sale securities, contractual maturities between 1 to 5 years	6,505	6,425
Available for sale securities, contractual maturities between 5 to 10 years	28,229	27,664
Available for sale securities, contractual maturities, Total	34,734	36,217
Asset Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities between 1 to 5 years	303	319
Available for sale securities, contractual maturities after 10 years	32,541	13,988
Available for sale securities, contractual maturities, Total	32,844	14,307
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	8,569	20,632
Available for sale securities, contractual maturities between 1 to 5 years	1,230	804
Available for sale securities, contractual maturities, Total	9,799	21,436
Supranational Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	4,842
Available for sale securities, contractual maturities between 1 to 5 years		4,800
Available for sale securities, contractual maturities, Total	$ 4,842	$ 4,800

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Mortgage Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Average contractual maturity period	17 years	17 years

Workers' Compensation Claims -

Workers' Compensation Claims - Summarizes Aggregate Workers' Compensation Reserve Activity (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Workers Compensation Reserve [Abstract]
Workers' compensation claims liabilities, Beginning balance	$ 438,986	$ 413,397
Add: claims expense accrual
Current period	38,492	40,385
Prior periods	(813)	(1,700)
Total expense accrual	37,679	38,685
Less: claim payments related to
Current period	1,550	1,459
Prior periods	29,677	27,716
Total paid	31,227	29,175
Change in claims incurred in excess of retention limits	(128)	(35)
Workers' compensation claims liabilities, Ending balance	445,310	422,872
Incurred but not reported (IBNR)	$ 282,497	$ 268,291
Ratio of IBNR to workers' compensation claims liabilities	63.00%	63.00%

Workers' Compensation Claims _2

Workers' Compensation Claims - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Worker's compensation risk claim maximum	$ 5,000,000
Surety bonds	15,000,000
Balance in Chubb trust accounts	411,100,000	$ 393,500,000
Collateral securities maintain to cover potential workers compensation claims losses	76,100,000	76,100,000
Surety bonds and standby letters of credit	76,100,000
Estimated future liability for unsettled workers' compensation	445,310,000	438,986,000	$ 422,872,000	$ 413,397,000
Reserves incurred in excess of retention limits	3,200,000	3,300,000
Other Assets [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrual for costs incurred in excess of retention limits offset by a receivable	3,200,000	$ 3,300,000
Wells Fargo Bank, National Association [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Letter of credit	63,700,000
Maryland [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reinsurance coverage	1,000,000
Colorado [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reinsurance coverage	2,000,000
California [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Surety bonds and standby letters of credit	$ 55,600,000

Revolving Credit Facility and_2

Revolving Credit Facility and Long-Term Debt - Additional Information (Detail) - Agreement [Member] - USD ($)	1 Months Ended		3 Months Ended
	May 31, 2020	Jun. 30, 2018	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	May 30, 2020	Dec. 31, 2019	Aug. 06, 2019	Aug. 05, 2019
Line of Credit Facility [Line Items]
Credit facility borrowing used						$ 5,800,000
Line of credit facility commitment fee description						The Agreement also provides for an unused commitment fee of 0.375% per year on the average daily unused amount of the revolving credit line, as well as a fee of 1.75% of the face amount of each letter of credit reserved under the line of credit.
Outstanding balance on term loan and revolving credit facility						$ 0		$ 0
Ratio of restricted and unrestricted cash and investments to workers' compensation and safety incentive liabilities						100.00%
Maximum amount to redeem retire repurchase or acquire stock upon agreement						$ 15,000,000
Scenario Forecast [Member]
Line of Credit Facility [Line Items]
Ratio of restricted and unrestricted cash and investments to workers' compensation and safety incentive liabilities			100.00%	100.00%	100.00%
Minimum [Member]
Line of Credit Facility [Line Items]
EBITDA						30,000,000
Minimum [Member] | Scenario Forecast [Member]
Line of Credit Facility [Line Items]
EBITDA			$ 30,000,000	$ 30,000,000	$ 30,000,000
Maximum [Member]
Line of Credit Facility [Line Items]
Prohibition on incurring additional indebtedness without the prior approval of the Bank in purchase money financing						$ 1,000,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility borrowing capacity									$ 33,000,000	$ 28,000,000
Credit facility, expiration date						Jul. 1, 2022
Unused commitment fee on unused amount during period						0.375%
Revolving Credit Facility [Member] | Scenario Forecast [Member]
Line of Credit Facility [Line Items]
Credit facility borrowing capacity	$ 50,000,000						$ 33,000,000
Credit facility, expiration date	Jul. 31, 2021
Revolving Credit Facility [Member] | Daily Floating Rate [Member]
Line of Credit Facility [Line Items]
Term loan from Bank, Interest rate description						the daily floating rate of one-month LIBOR plus 1.75% or (b) the fixed rate of LIBOR plus 1.75%
LIBOR plus rate						1.75%
Revolving Credit Facility [Member] | Fixed Rate [Member]
Line of Credit Facility [Line Items]
Term loan from Bank, Interest rate description						the fixed rate of LIBOR plus 1.75%
LIBOR plus rate						1.75%
Standby Letters of Credit [Member]
Line of Credit Facility [Line Items]
Credit facility borrowing capacity									$ 8,000,000	$ 7,500,000
Line of Credit [Member]
Line of Credit Facility [Line Items]
Unused commitment fee on unused amount						1.75%
Chubb Letter of Credit [Member]
Line of Credit Facility [Line Items]
Credit facility borrowing capacity						$ 63,700,000
Credit facility, expiration date						Jul. 1, 2020
Percentage of initial fee under letter of credit		2.50%				2.50%
Percentage of aggregate fee under letter of credit						95.00%
Percentage of annual fee under letter of credit						1.00%
Chubb Letter of Credit [Member] | Collateral Accounts [Member]
Line of Credit Facility [Line Items]
Percentage of deposit in collateral accounts						50.00%
Deposit in collateral accounts						$ 32,400,000
Chubb Letter of Credit [Member] | Collateral Accounts [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Deposit in collateral accounts						$ 16,000,000
Term Loan [Member]
Line of Credit Facility [Line Items]
Term loan from Bank, Interest rate description						one-month LIBOR plus 2.0%
Term loan with principal bank						$ 3,900,000		$ 4,000,000
Payment of monthly principal of term loan						$ 18,375
Term Loan [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
LIBOR plus rate						2.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020
Internal Revenue Service [Member]
Income Tax Contingency [Line Items]
Open tax years	2011 2012 2013 2014

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Agreement [Member] - Revolving Credit Facility [Member] - USD ($)	1 Months Ended	3 Months Ended
	May 31, 2020	Mar. 31, 2020	May 30, 2020	Aug. 06, 2019	Aug. 05, 2019
Subsequent Event [Line Items]
Credit facility borrowing capacity				$ 33,000,000	$ 28,000,000
Credit facility, expiration date		Jul. 1, 2022
Scenario Forecast [Member]
Subsequent Event [Line Items]
Credit facility borrowing capacity	$ 50,000,000		$ 33,000,000
Credit facility, expiration date	Jul. 31, 2021