Barrett Business Services (BBSI) 10-Q 6 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Nov. 01, 2019
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
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		7,494,281
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	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 35,452	$ 35,371
Investments	101,748	416
Trade accounts receivable, net	187,467	151,597
Prepaid expenses and other	15,974	13,880
Restricted cash and investments	107,702	120,409
Total current assets	448,343	321,673
Investments		1,687
Property, equipment and software, net	29,575	24,812
Operating lease right-of-use assets	23,784
Restricted cash and investments	311,882	348,165
Goodwill	47,820	47,820
Other assets	3,253	3,474
Deferred income taxes	5,523	8,458
Total assets	870,180	756,089
Current liabilities:
Current portion of long-term debt	221	221
Accounts payable	5,432	4,336
Accrued payroll, payroll taxes and related benefits	197,686	158,683
Income taxes payable	3,408	4,403
Current operating lease liabilities	6,448
Other accrued liabilities	13,244	20,566
Workers' compensation claims liabilities	113,623	109,319
Safety incentives liability	27,727	29,210
Total current liabilities	367,789	326,738
Long-term workers' compensation claims liabilities	316,423	304,078
Long-term debt	3,785	3,951
Long-term operating lease liabilities	17,906
Customer deposits and other long-term liabilities	4,106	2,285
Total liabilities	710,009	637,052
Commitments and contingencies (Notes 4, 5 and 7)
Stockholders' equity:
Common stock, $.01 par value; 20,500 shares authorized, 7,494 and 7,395 shares issued and outstanding	75	74
Additional paid-in capital	18,259	15,437
Accumulated other comprehensive income (loss)	2,619	(5,068)
Retained earnings	139,218	108,594
Total stockholders' equity	160,171	119,037
Total liabilities and stockholders' equity	$ 870,180	$ 756,089

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
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	7,494,000	7,395,000
Common stock, shares outstanding	7,494,000	7,395,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 247,962	$ 247,287	$ 697,159	$ 702,866
Cost of revenues:
Total cost of revenues	177,198	187,602	542,929	578,437
Gross margin	70,764	59,685	154,230	124,429
Selling, general and administrative expenses	41,352	36,670	113,517	101,713
Depreciation and amortization	970	949	2,909	3,228
Income from operations	28,442	22,066	37,804	19,488
Other income (expense):
Investment income, net	2,882	2,235	9,286	6,455
Interest expense	(394)	(465)	(1,352)	(574)
Other, net		10	12	15
Other income, net	2,488	1,780	7,946	5,896
Income before income taxes	30,930	23,846	45,750	25,384
Provision for income taxes	5,959	4,759	9,172	4,178
Net income	$ 24,971	$ 19,087	$ 36,578	$ 21,206
Basic income per common share	$ 3.34	$ 2.59	$ 4.92	$ 2.89
Weighted average number of basic common shares outstanding	7,483	7,369	7,433	7,327
Diluted income per common share	$ 3.24	$ 2.50	$ 4.76	$ 2.77
Weighted average number of diluted common shares outstanding	7,711	7,643	7,686	7,652
Professional Employer Service Fees [Member]
Revenues:
Total revenues	$ 214,156	$ 206,320	$ 607,840	$ 592,559
Staffing Services [Member]
Revenues:
Total revenues	33,806	40,967	89,319	110,307
Direct Payroll Costs [Member]
Cost of revenues:
Total cost of revenues	25,464	30,842	67,298	83,265
Payroll Taxes and Benefits [Member]
Cost of revenues:
Total cost of revenues	104,847	100,348	321,341	322,784
Workers' Compensation [Member]
Cost of revenues:
Total cost of revenues	$ 46,887	$ 56,412	$ 154,290	$ 172,388

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 24,971	$ 19,087	$ 36,578	$ 21,206
Unrealized gains (losses) on investments, net of tax	987	(1,037)	7,687	(5,976)
Comprehensive income	$ 25,958	$ 18,050	$ 44,265	$ 15,230

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Unrealized gains (losses) on investments, tax	$ 376	$ (396)	$ 2,935	$ (2,325)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Retained Earnings [Member]	Additional Paid-in Capital [Member]
Beginning balance at Dec. 31, 2017	$ 88,834	$ 73	$ (1,430)	$ 77,880	$ 12,311
Beginning balance, shares at Dec. 31, 2017		7,301
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	53				53
Common stock issued on exercise of options and vesting of restricted stock units and performance awards, shares		7
Common stock repurchased on vesting of restricted stock units and performance awards	(76)				(76)
Common stock repurchased on vesting of restricted stock units and performance awards, shares		(1)
Share-based compensation expense	1,542				1,542
Cash dividends on common stock	(1,826)			(1,826)
Unrealized gains (losses) on investments, net of tax	(3,964)		(3,964)
Net income (loss)	(9,123)			(9,123)
Ending balance at Mar. 31, 2018	75,440	$ 73	(5,394)	66,931	13,830
Ending balance, shares at Mar. 31, 2018		7,307
Beginning balance at Dec. 31, 2017	88,834	$ 73	(1,430)	77,880	12,311
Beginning balance, shares at Dec. 31, 2017		7,301
Unrealized gains (losses) on investments, net of tax	(5,976)
Net income (loss)	21,206
Ending balance at Sep. 30, 2018	99,929	$ 74	(7,406)	93,587	13,674
Ending balance, shares at Sep. 30, 2018		7,381
Beginning balance at Mar. 31, 2018	75,440	$ 73	(5,394)	66,931	13,830
Beginning balance, shares at Mar. 31, 2018		7,307
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	48				48
Common stock issued on exercise of options and vesting of restricted stock units and performance awards, shares		5
Common stock repurchased on vesting of restricted stock units and performance awards	(92)				(92)
Common stock repurchased on vesting of restricted stock units and performance awards, shares		(1)
Share-based compensation expense	1,041				1,041
Cash dividends on common stock	(1,827)			(1,827)
Unrealized gains (losses) on investments, net of tax	(975)		(975)
Net income (loss)	11,240			11,240
Ending balance at Jun. 30, 2018	84,875	$ 73	(6,369)	76,344	14,827
Ending balance, shares at Jun. 30, 2018		7,311
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	223	$ 1			222
Common stock issued on exercise of options and vesting of restricted stock units and performance awards, shares		100
Common stock repurchased on vesting of restricted stock units and performance awards	(2,784)				(2,784)
Common stock repurchased on vesting of restricted stock units and performance awards, shares		(30)
Share-based compensation expense	1,409				1,409
Cash dividends on common stock	(1,844)			(1,844)
Unrealized gains (losses) on investments, net of tax	(1,037)		(1,037)
Net income (loss)	19,087			19,087
Ending balance at Sep. 30, 2018	99,929	$ 74	(7,406)	93,587	13,674
Ending balance, shares at Sep. 30, 2018		7,381
Beginning balance at Dec. 31, 2018	119,037	$ 74	(5,068)	108,594	15,437
Beginning balance, shares at Dec. 31, 2018		7,395
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	122				122
Common stock issued on exercise of options 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 gains (losses) on investments, net of tax	3,657		3,657
Net income (loss)	(2,300)			(2,300)
Ending balance at Mar. 31, 2019	119,873	$ 74	(1,411)	104,442	16,768
Ending balance, shares at Mar. 31, 2019		7,410
Beginning balance at Dec. 31, 2018	119,037	$ 74	(5,068)	108,594	15,437
Beginning balance, shares at Dec. 31, 2018		7,395
Unrealized gains (losses) on investments, net of tax	7,687
Net income (loss)	36,578
Ending balance at Sep. 30, 2019	160,171	$ 75	2,619	139,218	18,259
Ending balance, shares at Sep. 30, 2019		7,494
Beginning balance at Mar. 31, 2019	119,873	$ 74	(1,411)	104,442	16,768
Beginning balance, shares at Mar. 31, 2019		7,410
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	56				56
Common stock issued on exercise of options and vesting of restricted stock units and performance awards, shares		4
Share-based compensation expense	2,441				2,441
Cash dividends on common stock	(1,853)			(1,853)
Unrealized gains (losses) on investments, net of tax	3,043		3,043
Net income (loss)	13,907			13,907
Ending balance at Jun. 30, 2019	137,467	$ 74	1,632	116,496	19,265
Ending balance, shares at Jun. 30, 2019		7,414
Common stock issued on exercise of options and vesting of restricted stock units and performance awards	280	$ 1			279
Common stock issued on exercise of options and vesting of restricted stock units and performance awards, shares		116
Common stock repurchased on vesting of restricted stock units and performance awards	(2,958)	$ (36)			(2,958)
Share-based compensation expense	1,673				1,673
Cash dividends on common stock	(2,249)			(2,249)
Unrealized gains (losses) on investments, net of tax	987		987
Net income (loss)	24,971			24,971
Ending balance at Sep. 30, 2019	$ 160,171	$ 75	$ 2,619	$ 139,218	$ 18,259
Ending balance, shares at Sep. 30, 2019		7,494

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Statement Of Stockholders Equity [Abstract]
Cash dividends on common stock per share	$ 0.30	$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 0.25

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 36,578	$ 21,206
Reconciliations of net income to net cash provided by operating activities:
Depreciation and amortization	2,909	3,228
Non-cash lease expense	5,243
Investment (accretion) amortization and (gains) losses recognized	940	36
Share-based compensation	5,501	3,992
Changes in certain operating assets and liabilities:
Trade accounts receivable	(35,870)	(25,910)
Income taxes receivable		1,686
Prepaid expenses and other	(2,094)	(6,720)
Accounts payable	1,096	(702)
Accrued payroll, payroll taxes and related benefits	40,763	13,079
Other accrued liabilities	(7,322)	(772)
Income taxes payable	(995)	2,429
Workers' compensation claims liabilities	16,857	35,391
Safety incentives liability	(1,483)	68
Operating lease liabilities	(4,673)
Other assets and liabilities, net	75	(109)
Net cash provided by operating activities	57,525	46,902
Cash flows from investing activities:
Purchase of property and equipment	(7,672)	(4,442)
Purchase of investments	(658)	(1,688)
Proceeds from sales and maturities of investments	15,941	1,481
Purchase of restricted investments	(3,946)	(103,861)
Proceeds from sales and maturities of restricted investments	42,409	54,819
Net cash provided by (used in) investing activities	46,074	(53,691)
Cash flows from financing activities:
Proceeds from credit-line borrowings	18,843	8,500
Payments on credit-line borrowings	(18,843)	(8,500)
Payments on long-term debt	(166)	(165)
Common stock repurchased on vesting of stock awards	(3,136)	(2,952)
Dividends paid	(5,954)	(5,499)
Proceeds from exercise of stock options	458	324
Net cash used in financing activities	(8,798)	(8,292)
Net increase (decrease) in cash, cash equivalents and restricted cash	94,801	(15,081)
Cash, cash equivalents and restricted cash, beginning of period	140,702	120,205
Cash, cash equivalents and restricted cash, end of period	$ 235,503	$ 105,124

Basis of Presentation of Interi

Basis of Presentation of Interim Period Statements	9 Months Ended
	Sep. 30, 2019
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 2018 Annual Report on Form 10-K at pages F1 – F27. 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 customer incentives, including safety incentives, because those 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 duration and extent to which fair value is less than cost. Realized gains and losses on sales of investments are included in investment income in our condensed consolidated statements of operations. In the event a loss is determined to be other-than-temporary, the loss will be recognized in the 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 duration and extent to which fair value is less than cost. Realized gains and losses on sales of restricted investments are included in investment income in our condensed consolidated statements of operations. In the event a loss is determined to be other-than-temporary, the loss will be recognized in the 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 other income (expense), net. Allowance for doubtful accounts The Company had an allowance for doubtful accounts of $774,000 and $533,000 at September 30, 2019 and December 31, 2018, respectively. We make estimates of the collectability of our accounts receivable for services provided to our customers. 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 administrators for workers’ compensation claims, coupled with an actuarial estimate of future adverse 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, and unallocated loss adjustment expenses. 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. 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. Customer incentives We accrue for and present expected customer 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 nine months ended September 30, 2019 did not materially differ from interest expense. Interest paid during the nine months ended September 30, 2018 totaled $1.8 million, primarily related to prepaid fees for the Company’s letter of credit. Income taxes paid during the nine months ended September 30, 2019 totaled $10.1 million . 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): September 30, December 31, September 30, December 31, 2019 2018 2018 2017 Cash and cash equivalents $ 35,452 $ 35,371 $ 34,975 $ 59,835 Restricted cash, included in restricted cash and investments 200,051 105,331 70,149 60,370 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 235,503 $ 140,702 $ 105,124 $ 120,205 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 Nine Months Ended September 30, September 30, 2019 2018 2019 2018 Weighted average number of basic shares outstanding 7,483 7,369 7,433 7,327 Effect of dilutive securities 228 274 253 325 Weighted average number of diluted shares outstanding 7,711 7,643 7,686 7,652 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 and equipment, accrued workers’ compensation liabilities and customer incentive liabilities. Actual results may or may not differ from such estimates. Recent accounting pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-02, “Leases.” The core principle is that a lessee should recognize the assets and liabilities that arise from leases, including operating leases. Under the new guidance, a lessee should recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. The amendments in this update were adopted using the optional transition method, effective January 1, 2019. The lease commitments appear on our condensed consolidated balance sheets as operating lease right-of-use assets and current and long-term operating lease liabilities. Such amounts are based on the present value of such commitments using our incremental borrowing rate. We have utilized the transition package of practical expedients permitted within the new standard, which allows us to carry forward the historical lease classification. See “Note 5 – Leases” for additional information.

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurement	Note 2 - Fair Value Measurement The following table summarizes the Company’s investments at September 30, 2019 and December 31, 2018 measured at fair value on a recurring basis (in thousands): September 30, 2019 December 31, 2018 Gross Gross Unrealized Unrealized Gains Recorded Gains Recorded Cost (Losses) Basis Cost (Losses) Basis Current: Cash equivalents: Money market funds $ 6,121 $ — $ 6,121 $ 30 $ — $ 30 Total cash equivalents 6,121 — 6,121 30 — 30 Investments: Corporate bonds 70,922 36 70,958 20 — 20 U.S. treasuries 18,642 (27 ) 18,615 347 — 347 U.S. government agency securities 8,910 313 9,223 50 (1 ) 49 Mortgage backed securities 2,943 (8 ) 2,935 — — — Asset backed securities 17 — 17 — — — Total current investments 101,434 314 101,748 417 (1 ) 416 Long term: Investments: U.S. treasuries — — — 794 (3 ) 791 Mortgage backed securities — — — 484 (13 ) 471 Corporate bonds — — — 422 (7 ) 415 Asset backed securities — — — 10 — 10 Total long term investments — — — 1,710 (23 ) 1,687 Restricted cash and investments (1) Corporate bonds 101,533 1,793 103,326 185,116 (3,739 ) 181,377 Mortgage backed securities 66,012 507 66,519 89,426 (2,026 ) 87,400 U.S. government agency securities 29,780 947 30,727 45,548 (908 ) 44,640 Money market funds 19,085 (2 ) 19,083 419 — 419 U.S. treasuries 18,397 24 18,421 44,304 (283 ) 44,021 Supranational bonds 4,769 33 4,802 4,765 (24 ) 4,741 Mutual funds 2,844 — 2,844 1,093 — 1,093 Asset backed securities 116 1 117 75 (1 ) 74 Municipal bonds 50 — 50 50 — 50 Total restricted cash and investments 242,586 3,303 245,889 370,796 (6,981 ) 363,815 Total investments $ 350,141 $ 3,617 $ 353,758 $ 372,953 $ (7,005 ) $ 365,948 (1) Included in restricted cash and investments within the condensed consolidated balance sheet is restricted cash of $173.7 million and $104.5 million as of September 30, 2019 and December 31, 2018, 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 September 30, 2019 and December 31, 2018 measured at fair value on a recurring basis by fair value hierarchy level (in thousands): September 30, 2019 December 31, 2018 Total Total Recorded Recorded Basis Level 1 Level 2 Other (1) Basis Level 1 Level 2 Other (1) Cash equivalents: Money market funds $ 6,121 $ — $ — $ 6,121 $ 30 $ — $ — $ 30 Investments: Corporate bonds 70,958 — 70,958 — 435 — 435 — U.S. treasuries 18,615 — 18,615 — 1,138 — 1,138 — U.S. government agency securities 9,223 — 9,223 — 49 — 49 — Mortgage backed securities 2,935 — 2,935 — 471 — 471 — Asset backed securities 17 — 17 — 10 — 10 — Restricted cash and investments: Corporate bonds 103,326 — 103,326 — 181,377 — 181,377 — Mortgage backed securities 66,519 — 66,519 — 87,400 — 87,400 — U.S. government agency securities 30,727 — 30,727 — 44,640 — 44,640 — Money market funds 19,083 — — 19,083 419 — — 419 U.S. treasuries 18,421 — 18,421 — 44,021 — 44,021 — Supranational bonds 4,802 — 4,802 — 4,741 — 4,741 — Mutual funds 2,844 2,844 — — 1,093 1,093 — — Asset backed securities 117 — 117 — 74 — 74 — Municipal bonds 50 — 50 — 50 — 50 — Total investments $ 353,758 $ 2,844 $ 325,710 $ 25,204 $ 365,948 $ 1,093 $ 364,406 $ 449 The following table summarizes the contractual maturities of the Company’s available for sale securities at September 30, 2019. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties. September 30, 2019 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 30,040 $ 122,786 $ 21,458 $ — $ 174,284 U.S. government agency securities 5,499 6,443 28,008 — $ 39,950 U.S. treasuries 36,232 804 — — $ 37,036 Money market funds 25,204 — — — $ 25,204 Supranational bonds — 4,802 — — $ 4,802 Asset backed securities — 134 — — $ 134 Municipal bonds 50 — — — $ 50 Total $ 97,025 $ 134,969 $ 49,466 $ - $ 281,460 The average contractual maturity of mortgage backed securities was 17 years as of September 30, 2019.

Workers' Compensation Claims

Workers' Compensation Claims	9 Months Ended
	Sep. 30, 2019
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 Nine Months Ended September 30, September 30, 2019 2018 2019 2018 Beginning balance Workers' compensation claims liabilities $ 430,736 $ 390,814 $ 413,397 $ 363,517 Add: claims expense accrual Current period 37,404 37,784 118,934 116,803 Prior periods (5,593 ) (2,327 ) (10,245 ) (2,333 ) 31,811 35,457 108,689 114,470 Less: claim payments related to Current period 8,609 7,502 14,213 13,783 Prior periods 23,815 19,905 77,619 65,296 32,424 27,407 91,832 79,079 Change in claims incurred in excess of retention limits (77 ) (26 ) (208 ) (70 ) Ending balance Workers' compensation claims liabilities $ 430,046 $ 398,838 $ 430,046 $ 398,838 Incurred but not reported (IBNR) $ 274,344 $ 246,174 $ 274,344 $ 246,174 Ratio of IBNR to workers' compensation claims liabilities 64 % 62 % 64 % 62 % 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 the Company 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 $74.8 The Company provided a total of $430.0 million and $413.4 million at September 30, 2019 and December 31, 2018, respectively, as an estimated future liability for unsettled workers' compensation claims liabilities. Of this amount, $3.0 million and $3.2 million at September 30, 2019 and December 31, 2018, 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 $3.0 million and $3.2 million at September 30, 2019 and December 31, 2018, respectively, included in other assets on the condensed consolidated balance sheets.

Revolving Credit Facility and L

Revolving Credit Facility and Long-Term Debt	9 Months Ended
	Sep. 30, 2019
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 supersedes 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 September 30, 2019, $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. In connection with the Chubb Letter of Credit, 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 third quarter of 2019, the Company has deposited $18.1 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; and • the Company may not terminate or cancel any of the AICE policies 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 September 30, 2019, the Company was in compliance with all covenants. The Company maintains a mortgage loan with the Bank with a balance of approximately $4.0 million and $4.2 million at September 30, 2019 and December 31, 2018, 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

Leases

Leases	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Leases	Note 5 – Leases Effective January 1, 2019, the Company adopted Accounting Standards Codification (“ASC”) Topic 842 “Leases” using the optional transition method. Under this method of adoption, the prior period comparative information in the consolidated financial statements has not been revised and continues to be reported under the previously applicable lease accounting guidance. Additionally, we elected the package of practical expedients permitted under the transition guidance, which included the carry-forward of historical lease classification. The Company primarily leases office buildings under operating leases which are included in Operating lease right-of-use (“ROU”) assets, Current operating lease liabilities, and Long-term operating lease liabilities on the condensed consolidated balance sheets. The Company’s leases have remaining terms of 1 to 7 years and often include one or more options to renew. The Company evaluates renewal options at lease inception and on an ongoing basis and includes renewal options that it is reasonably certain to exercise in its expected lease terms when classifying leases and measuring liabilities. Leases with initial terms of 12 months or less are considered short-term lease costs and are not recorded as ROU assets on the condensed consolidated balance sheets. The Company has elected the practical expedient not to separate non-lease components from lease components for all classes of assets. Our lease agreements contain $3.7 million of residual value guarantees and generally do not contain material variable lease payments or restrictive covenants. Information related to the Company's total lease costs were as follows (in thousands): Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Operating lease cost $ 2,438 $ 6,040 Variable lease cost 500 750 Short-term lease cost 198 442 Total lease cost $ 3,136 $ 7,232 Information related to the Company's ROU assets and related lease liabilities were as follows (in thousands): Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Cash paid for operating lease liabilities $ 1,916 $ 5,561 Right-of-use assets obtained in exchange for new operating lease obligations (1) 513 29,028 (1) Nine-months ended balance includes $25.8 million for operating leases existing on January 1, 2019 and $3.2 As of September 30, 2019 Weighted-average remaining lease term 4.0 years Weighted-average discount rate 4.4 % The table below reconciles the undiscounted future minimum lease payments (displayed by year and in the aggregate) under noncancellable operating leases with terms of more than one year to the total operating lease liabilities recognized on the condensed consolidated balance sheets as of September 30, 2019 (in thousands): October 1, 2019 through December 31, 2019 $ 1,910 2020 7,227 2021 6,606 2022 5,089 2023 3,720 Thereafter 2,116 Total undiscounted future minimum lease payments 26,668 Less: Difference between undiscounted lease payments and discounted operating lease liabilities 2,314 Total operating lease liabilities $ 24,354 Current operating lease liabilities $ 6,448 Long-term operating lease liabilities 17,906 Total operating lease liabilities $ 24,354 As previously disclosed in our 2018 Annual Report on Form 10-K, under the previous lease accounting standard, future minimum lease payments for operating leases having initial or remaining noncancellable lease terms in excess of one year would have been as follows (in thousands): Year Ending December 31, 2019 $ 7,135 2020 6,198 2021 5,673 2022 4,125 2023 2,642 Thereafter 1,474 $ 27,247

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Note 6 – Income Taxes 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. 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 September 30, 2019. 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 years before 2011. 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	9 Months Ended
	Sep. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Litigation	Note 7 – 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	9 Months Ended
	Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Events	Note 8 – Subsequent Events We have evaluated events and transactions occurring after the balance sheet date through our filing date and noted no events that are subject to recognition or disclosure.

Basis of Presentation of Inte_2

Basis of Presentation of Interim Period Statements (Policies)	9 Months Ended
	Sep. 30, 2019
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 customer incentives, including safety incentives, because those 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 duration and extent to which fair value is less than cost. Realized gains and losses on sales of investments are included in investment income in our condensed consolidated statements of operations. In the event a loss is determined to be other-than-temporary, the loss will be recognized in the 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 duration and extent to which fair value is less than cost. Realized gains and losses on sales of restricted investments are included in investment income in our condensed consolidated statements of operations. In the event a loss is determined to be other-than-temporary, the loss will be recognized in the 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 other income (expense), net.
Allowance for doubtful accounts	Allowance for doubtful accounts The Company had an allowance for doubtful accounts of $774,000 and $533,000 at September 30, 2019 and December 31, 2018, respectively. We make estimates of the collectability of our accounts receivable for services provided to our customers. 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 administrators for workers’ compensation claims, coupled with an actuarial estimate of future adverse 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, and unallocated loss adjustment expenses. 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. 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.
Customer incentives	Customer incentives We accrue for and present expected customer 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 nine months ended September 30, 2019 did not materially differ from interest expense. Interest paid during the nine months ended September 30, 2018 totaled $1.8 million, primarily related to prepaid fees for the Company’s letter of credit. Income taxes paid during the nine months ended September 30, 2019 totaled $10.1 million . 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): September 30, December 31, September 30, December 31, 2019 2018 2018 2017 Cash and cash equivalents $ 35,452 $ 35,371 $ 34,975 $ 59,835 Restricted cash, included in restricted cash and investments 200,051 105,331 70,149 60,370 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 235,503 $ 140,702 $ 105,124 $ 120,205
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 Nine Months Ended September 30, September 30, 2019 2018 2019 2018 Weighted average number of basic shares outstanding 7,483 7,369 7,433 7,327 Effect of dilutive securities 228 274 253 325 Weighted average number of diluted shares outstanding 7,711 7,643 7,686 7,652
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 and equipment, accrued workers’ compensation liabilities and customer incentive liabilities. Actual results may or may not differ from such estimates.
Recent accounting pronouncements	Recent accounting pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2016-02, “Leases.” The core principle is that a lessee should recognize the assets and liabilities that arise from leases, including operating leases. Under the new guidance, a lessee should recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize lease assets and lease liabilities. The amendments in this update were adopted using the optional transition method, effective January 1, 2019. The lease commitments appear on our condensed consolidated balance sheets as operating lease right-of-use assets and current and long-term operating lease liabilities. Such amounts are based on the present value of such commitments using our incremental borrowing rate. We have utilized the transition package of practical expedients permitted within the new standard, which allows us to carry forward the historical lease classification. See “Note 5 – Leases” for additional information.

Basis of Presentation of Inte_3

Basis of Presentation of Interim Period Statements (Tables)	9 Months Ended
	Sep. 30, 2019
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): September 30, December 31, September 30, December 31, 2019 2018 2018 2017 Cash and cash equivalents $ 35,452 $ 35,371 $ 34,975 $ 59,835 Restricted cash, included in restricted cash and investments 200,051 105,331 70,149 60,370 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 235,503 $ 140,702 $ 105,124 $ 120,205
Summary of Basic and Diluted Common Shares Outstanding	Basic and diluted shares outstanding are summarized as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 Weighted average number of basic shares outstanding 7,483 7,369 7,433 7,327 Effect of dilutive securities 228 274 253 325 Weighted average number of diluted shares outstanding 7,711 7,643 7,686 7,652

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Summary of Investments Measured at Fair Value on Recurring Basis	The following table summarizes the Company’s investments at September 30, 2019 and December 31, 2018 measured at fair value on a recurring basis (in thousands): September 30, 2019 December 31, 2018 Gross Gross Unrealized Unrealized Gains Recorded Gains Recorded Cost (Losses) Basis Cost (Losses) Basis Current: Cash equivalents: Money market funds $ 6,121 $ — $ 6,121 $ 30 $ — $ 30 Total cash equivalents 6,121 — 6,121 30 — 30 Investments: Corporate bonds 70,922 36 70,958 20 — 20 U.S. treasuries 18,642 (27 ) 18,615 347 — 347 U.S. government agency securities 8,910 313 9,223 50 (1 ) 49 Mortgage backed securities 2,943 (8 ) 2,935 — — — Asset backed securities 17 — 17 — — — Total current investments 101,434 314 101,748 417 (1 ) 416 Long term: Investments: U.S. treasuries — — — 794 (3 ) 791 Mortgage backed securities — — — 484 (13 ) 471 Corporate bonds — — — 422 (7 ) 415 Asset backed securities — — — 10 — 10 Total long term investments — — — 1,710 (23 ) 1,687 Restricted cash and investments (1) Corporate bonds 101,533 1,793 103,326 185,116 (3,739 ) 181,377 Mortgage backed securities 66,012 507 66,519 89,426 (2,026 ) 87,400 U.S. government agency securities 29,780 947 30,727 45,548 (908 ) 44,640 Money market funds 19,085 (2 ) 19,083 419 — 419 U.S. treasuries 18,397 24 18,421 44,304 (283 ) 44,021 Supranational bonds 4,769 33 4,802 4,765 (24 ) 4,741 Mutual funds 2,844 — 2,844 1,093 — 1,093 Asset backed securities 116 1 117 75 (1 ) 74 Municipal bonds 50 — 50 50 — 50 Total restricted cash and investments 242,586 3,303 245,889 370,796 (6,981 ) 363,815 Total investments $ 350,141 $ 3,617 $ 353,758 $ 372,953 $ (7,005 ) $ 365,948 (1) Included in restricted cash and investments within the condensed consolidated balance sheet is restricted cash of $173.7 million and $104.5 million as of September 30, 2019 and December 31, 2018, 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 September 30, 2019 and December 31, 2018 measured at fair value on a recurring basis by fair value hierarchy level (in thousands): September 30, 2019 December 31, 2018 Total Total Recorded Recorded Basis Level 1 Level 2 Other (1) Basis Level 1 Level 2 Other (1) Cash equivalents: Money market funds $ 6,121 $ — $ — $ 6,121 $ 30 $ — $ — $ 30 Investments: Corporate bonds 70,958 — 70,958 — 435 — 435 — U.S. treasuries 18,615 — 18,615 — 1,138 — 1,138 — U.S. government agency securities 9,223 — 9,223 — 49 — 49 — Mortgage backed securities 2,935 — 2,935 — 471 — 471 — Asset backed securities 17 — 17 — 10 — 10 — Restricted cash and investments: Corporate bonds 103,326 — 103,326 — 181,377 — 181,377 — Mortgage backed securities 66,519 — 66,519 — 87,400 — 87,400 — U.S. government agency securities 30,727 — 30,727 — 44,640 — 44,640 — Money market funds 19,083 — — 19,083 419 — — 419 U.S. treasuries 18,421 — 18,421 — 44,021 — 44,021 — Supranational bonds 4,802 — 4,802 — 4,741 — 4,741 — Mutual funds 2,844 2,844 — — 1,093 1,093 — — Asset backed securities 117 — 117 — 74 — 74 — Municipal bonds 50 — 50 — 50 — 50 — Total investments $ 353,758 $ 2,844 $ 325,710 $ 25,204 $ 365,948 $ 1,093 $ 364,406 $ 449
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 September 30, 2019. Actual maturities may differ from contractual maturities because borrowers may have the right to prepay obligations with or without prepayment penalties. September 30, 2019 (In thousands) Less than 1 Year Between 1 to 5 Years Between 5 to 10 Years After 10 Years Total Corporate bonds $ 30,040 $ 122,786 $ 21,458 $ — $ 174,284 U.S. government agency securities 5,499 6,443 28,008 — $ 39,950 U.S. treasuries 36,232 804 — — $ 37,036 Money market funds 25,204 — — — $ 25,204 Supranational bonds — 4,802 — — $ 4,802 Asset backed securities — 134 — — $ 134 Municipal bonds 50 — — — $ 50 Total $ 97,025 $ 134,969 $ 49,466 $ - $ 281,460

Workers' Compensation Claims (T

Workers' Compensation Claims (Tables)	9 Months Ended
	Sep. 30, 2019
Text Block [Abstract]
Summarizes Aggregate Workers' Compensation Reserve Activity	The following table summarizes the aggregate workers’ compensation reserve activity (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 Beginning balance Workers' compensation claims liabilities $ 430,736 $ 390,814 $ 413,397 $ 363,517 Add: claims expense accrual Current period 37,404 37,784 118,934 116,803 Prior periods (5,593 ) (2,327 ) (10,245 ) (2,333 ) 31,811 35,457 108,689 114,470 Less: claim payments related to Current period 8,609 7,502 14,213 13,783 Prior periods 23,815 19,905 77,619 65,296 32,424 27,407 91,832 79,079 Change in claims incurred in excess of retention limits (77 ) (26 ) (208 ) (70 ) Ending balance Workers' compensation claims liabilities $ 430,046 $ 398,838 $ 430,046 $ 398,838 Incurred but not reported (IBNR) $ 274,344 $ 246,174 $ 274,344 $ 246,174 Ratio of IBNR to workers' compensation claims liabilities 64 % 62 % 64 % 62 %

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Summary of Lease Costs	Information related to the Company's total lease costs were as follows (in thousands): Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Operating lease cost $ 2,438 $ 6,040 Variable lease cost 500 750 Short-term lease cost 198 442 Total lease cost $ 3,136 $ 7,232
Summary of Information Related to ROU Assets and Related Lease Liabilities	Information related to the Company's ROU assets and related lease liabilities were as follows (in thousands): Three Months Ended Nine Months Ended September 30, 2019 September 30, 2019 Cash paid for operating lease liabilities $ 1,916 $ 5,561 Right-of-use assets obtained in exchange for new operating lease obligations (1) 513 29,028 (1) Nine-months ended balance includes $25.8 million for operating leases existing on January 1, 2019 and $3.2 As of September 30, 2019 Weighted-average remaining lease term 4.0 years Weighted-average discount rate 4.4 %
Reconciliation of Undiscounted Future Minimum Lease Payments Under Noncancellable Operating Leases	The table below reconciles the undiscounted future minimum lease payments (displayed by year and in the aggregate) under noncancellable operating leases with terms of more than one year to the total operating lease liabilities recognized on the condensed consolidated balance sheets as of September 30, 2019 (in thousands): October 1, 2019 through December 31, 2019 $ 1,910 2020 7,227 2021 6,606 2022 5,089 2023 3,720 Thereafter 2,116 Total undiscounted future minimum lease payments 26,668 Less: Difference between undiscounted lease payments and discounted operating lease liabilities 2,314 Total operating lease liabilities $ 24,354 Current operating lease liabilities $ 6,448 Long-term operating lease liabilities 17,906 Total operating lease liabilities $ 24,354
Summary of Future Minimum Lease Payments for Operating Leases	As previously disclosed in our 2018 Annual Report on Form 10-K, under the previous lease accounting standard, future minimum lease payments for operating leases having initial or remaining noncancellable lease terms in excess of one year would have been as follows (in thousands): Year Ending December 31, 2019 $ 7,135 2020 6,198 2021 5,673 2022 4,125 2023 2,642 Thereafter 1,474 $ 27,247

Basis of Presentation of Inte_4

Basis of Presentation of Interim Period Statements - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2019USD ($)Company	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
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	$ 774,000		$ 533,000
Estimate of liability for unpaid safety incentives	27,700,000		29,200,000
One-time customer Incentive	5,000,000		$ 9,800,000
Interest paid		$ 1,800,000
Income taxes paid	$ 10,100,000	$ 100,000

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	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 35,452	$ 35,371	$ 34,975	$ 59,835
Restricted cash, included in restricted cash and investments	200,051	105,331	70,149	60,370
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$ 235,503	$ 140,702	$ 105,124	$ 120,205

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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Weighted Average Number Of Shares Outstanding Diluted Disclosure Items [Abstract]
Weighted average number of basic shares outstanding	7,483	7,369	7,433	7,327
Effect of dilutive securities	228	274	253	325
Weighted average number of diluted shares outstanding	7,711	7,643	7,686	7,652

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	$ 350,141	$ 372,953
Gross Unrealized Gains (Losses)	3,617	(7,005)
Recorded Basis	353,758	365,948
Investments Current [Member] | Cash and Cash Equivalents [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	6,121	30
Recorded Basis	6,121	30
Investments Current [Member] | Cash and Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	6,121	30
Recorded Basis	6,121	30
Investments Current [Member] | Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	101,434	417
Gross Unrealized Gains (Losses)	314	(1)
Recorded Basis	101,748	416
Investments Current [Member] | Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	70,922	20
Gross Unrealized Gains (Losses)	36
Recorded Basis	70,958	20
Investments Current [Member] | Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	18,642	347
Gross Unrealized Gains (Losses)	(27)
Recorded Basis	18,615	347
Investments Current [Member] | Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	8,910	50
Gross Unrealized Gains (Losses)	313	(1)
Recorded Basis	9,223	49
Investments Current [Member] | Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,943
Gross Unrealized Gains (Losses)	(8)
Recorded Basis	2,935
Investments Current [Member] | Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	17
Recorded Basis	17
Investments Noncurrent [Member] | Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost		1,710
Gross Unrealized Gains (Losses)		(23)
Recorded Basis		1,687
Investments Noncurrent [Member] | Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost		422
Gross Unrealized Gains (Losses)		(7)
Recorded Basis		415
Investments Noncurrent [Member] | Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost		794
Gross Unrealized Gains (Losses)		(3)
Recorded Basis		791
Investments Noncurrent [Member] | Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost		484
Gross Unrealized Gains (Losses)		(13)
Recorded Basis		471
Investments Noncurrent [Member] | Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost		10
Recorded Basis		10
Investments Noncurrent [Member] | Restricted Cash and Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	242,586	370,796
Gross Unrealized Gains (Losses)	3,303	(6,981)
Recorded Basis	245,889	363,815
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Money Market Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	19,085	419
Gross Unrealized Gains (Losses)	(2)
Recorded Basis	19,083	419
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	101,533	185,116
Gross Unrealized Gains (Losses)	1,793	(3,739)
Recorded Basis	103,326	181,377
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	18,397	44,304
Gross Unrealized Gains (Losses)	24	(283)
Recorded Basis	18,421	44,021
Investments Noncurrent [Member] | 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	29,780	45,548
Gross Unrealized Gains (Losses)	947	(908)
Recorded Basis	30,727	44,640
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	66,012	89,426
Gross Unrealized Gains (Losses)	507	(2,026)
Recorded Basis	66,519	87,400
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	116	75
Gross Unrealized Gains (Losses)	1	(1)
Recorded Basis	117	74
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	2,844	1,093
Recorded Basis	2,844	1,093
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Supranational Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	4,769	4,765
Gross Unrealized Gains (Losses)	33	(24)
Recorded Basis	4,802	4,741
Investments Noncurrent [Member] | Restricted Cash and Investments [Member] | Municipal Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cost	50	50
Recorded Basis	$ 50	$ 50

Fair Value Measurement - Summ_2

Fair Value Measurement - Summary of Investments Measured at Fair Value on Recurring Basis (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Restricted cash	$ 173.7	$ 104.5

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	Sep. 30, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	$ 353,758	$ 365,948
Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	25,204	449
Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,844	1,093
Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	325,710	364,406
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	6,121	30
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	6,121	30
Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	70,958	435
Investments [Member] | Corporate Bonds [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	70,958	435
Investments [Member] | Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,935	471
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	2,935	471
Investments [Member] | U.S. Treasuries [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	18,615	1,138
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	18,615	1,138
Investments [Member] | U.S. Government Agency Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	9,223	49
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	9,223	49
Investments [Member] | Asset Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	17	10
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	17	10
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	19,083	419
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	19,083	419
Restricted Cash and Investments [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	103,326	181,377
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	103,326	181,377
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	66,519	87,400
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	66,519	87,400
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	18,421	44,021
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	18,421	44,021
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	30,727	44,640
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	30,727	44,640
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	117	74
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	117	74
Restricted Cash and Investments [Member] | Mutual Funds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	2,844	1,093
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	2,844	1,093
Restricted Cash and Investments [Member] | Supranational Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	4,802	4,741
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	4,802	4,741
Restricted Cash and Investments [Member] | Municipal Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	50	50
Restricted Cash and Investments [Member] | Municipal Bonds [Member] | Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Recorded Basis	$ 50	$ 50

Fair Value Measurement - Summ_4

Fair Value Measurement - Summary of Contractual Maturities of Available for Sale Securities (Detail) $ in Thousands	Sep. 30, 2019USD ($)
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	$ 97,025
Available for sale securities, contractual maturities between 1 to 5 years	134,969
Available for sale securities, contractual maturities between 5 to 10 years	49,466
Available for sale securities, contractual maturities, Total	281,460
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	30,040
Available for sale securities, contractual maturities between 1 to 5 years	122,786
Available for sale securities, contractual maturities between 5 to 10 years	21,458
Available for sale securities, contractual maturities, Total	174,284
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	36,232
Available for sale securities, contractual maturities between 1 to 5 years	804
Available for sale securities, contractual maturities, Total	37,036
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	5,499
Available for sale securities, contractual maturities between 1 to 5 years	6,443
Available for sale securities, contractual maturities between 5 to 10 years	28,008
Available for sale securities, contractual maturities, Total	39,950
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	25,204
Available for sale securities, contractual maturities, Total	25,204
Supranational Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities between 1 to 5 years	4,802
Available for sale securities, contractual maturities, Total	4,802
Asset Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities between 1 to 5 years	134
Available for sale securities, contractual maturities, Total	134
Municipal Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	50
Available for sale securities, contractual maturities, Total	$ 50

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2019
Mortgage Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Average contractual maturity period	17 years

Workers' Compensation Claims -

Workers' Compensation Claims - Summarizes Aggregate Workers' Compensation Reserve Activity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Workers Compensation Reserve [Abstract]
Workers' compensation claims liabilities, Beginning balance	$ 430,736	$ 390,814	$ 413,397	$ 363,517
Add: claims expense accrual
Current period	37,404	37,784	118,934	116,803
Prior periods	(5,593)	(2,327)	(10,245)	(2,333)
Total expense accrual	31,811	35,457	108,689	114,470
Less: claim payments related to
Current period	8,609	7,502	14,213	13,783
Prior periods	23,815	19,905	77,619	65,296
Total paid	32,424	27,407	91,832	79,079
Change in claims incurred in excess of retention limits	(77)	(26)	(208)	(70)
Workers' compensation claims liabilities, Ending balance	430,046	398,838	430,046	398,838
Incurred but not reported (IBNR)	$ 274,344	$ 246,174	$ 274,344	$ 246,174
Ratio of IBNR to workers' compensation claims liabilities	64.00%	62.00%	64.00%	62.00%

Workers' Compensation Claims _2

Workers' Compensation Claims - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
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	380,600,000	$ 451,000,000
Collateral securities maintain to cover potential workers compensation claims losses	74,800,000	85,200,000
Surety bonds and standby letters of credit	74,800,000
Estimated future liability for unsettled workers' compensation	430,046,000	413,397,000	$ 430,736,000	$ 398,838,000	$ 390,814,000	$ 363,517,000
Reserves incurred in excess of retention limits	3,000,000	3,200,000
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	3,000,000	$ 3,200,000
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				9 Months Ended
	Jun. 30, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2019	Aug. 06, 2019	Aug. 05, 2019	Dec. 31, 2018
Line of Credit Facility [Line Items]
Credit facility borrowing used			$ 5,800,000			$ 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			$ 0
Ratio of restricted and unrestricted cash and investments to workers' compensation and safety incentive liabilities			100.00%	100.00%	100.00%
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%
Minimum [Member]
Line of Credit Facility [Line Items]
EBITDA			$ 30,000,000	$ 30,000,000	$ 30,000,000	30,000,000
Minimum [Member] | Scenario Forecast [Member]
Line of Credit Facility [Line Items]
EBITDA		$ 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] | 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%
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			$ 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%			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			$ 18,100,000			$ 18,100,000
Chubb Letter of Credit [Member] | Collateral Accounts [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Deposit in collateral accounts			16,000,000			$ 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			$ 4,000,000			$ 4,000,000			$ 4,200,000
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%

Leases - Additional Information

Leases - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Lessee Lease Description [Line Items]
Residual value of leased asset	$ 3.7
Minimum [Member]
Lessee Lease Description [Line Items]
Remaining lease term, operating lease	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Remaining lease term, operating lease	7 years

Leases - Summary of Lease Costs

Leases - Summary of Lease Costs (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lease Cost [Abstract]
Operating lease cost	$ 2,438	$ 6,040
Variable lease cost	500	750
Short-term lease cost	198	442
Total lease cost	$ 3,136	$ 7,232

Leases - Summary of Information

Leases - Summary of Information Related to ROU Assets and Related Lease Liabilities (Detail) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019	Sep. 30, 2019
Assets And Liabilities Lessee [Abstract]
Cash paid for operating lease liabilities		$ 1,916	$ 5,561
Right-of-use assets obtained in exchange for new operating lease obligations	$ 25,800	$ 513	$ 29,028
Weighted-average remaining lease term		4 years	4 years
Weighted-average discount rate		4.40%	4.40%

Leases - Summary of Informati_2

Leases - Summary of Information Related to ROU Assets and Related Lease Liabilities (Parenthetical) (Detail) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019	Sep. 30, 2019
Lessee Lease Description [Line Items]
Operating lease	$ 25,800	$ 513	$ 29,028
ASU 2016-02 [Member]
Lessee Lease Description [Line Items]
Operating lease			$ 3,200

Leases - Reconciliation of Undi

Leases - Reconciliation of Undiscounted Future Minimum Lease Payments Under Noncancellable Operating Leases (Detail) $ in Thousands	Sep. 30, 2019USD ($)
Operating Lease Liabilities Payments Due [Abstract]
October 1, 2019 through December 31, 2019	$ 1,910
2020	7,227
2021	6,606
2022	5,089
2023	3,720
Thereafter	2,116
Total undiscounted future minimum lease payments	26,668
Less: Difference between undiscounted lease payments and discounted operating lease liabilities	2,314
Total operating lease liabilities	24,354
Current operating lease liabilities	6,448
Long-term operating lease liabilities	$ 17,906

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Lease Payments for Operating Leases (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leases Future Minimum Payments Due [Abstract]
2019	$ 7,135
2020	6,198
2021	5,673
2022	4,125
2023	2,642
Thereafter	1,474
Total	$ 27,247

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2019
Internal Revenue Service [Member]
Income Tax Contingency [Line Items]
Open tax years	2011 2012 2013 2014