Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Allowance for Expected Credit Losses on Accounts Receivable

The allowance for expected credit losses on accounts receivable for the twelve months ended December 31, 2020 is summarized as follows (in thousands):

	Total Allowance
Balance at December 31, 2019	$	628
Cumulative effect adjustment of adopting Topic 326		218
Provision for expected credit losses		721
Write-offs		(850	)
Translation adjustments		(9	)
Balance at December 31, 2020	$	708

Summary of End-of-period Cash and Cash Equivalents and Cash, Cash Equivalents and Restricted Cash from Financial Statements

The following table summarizes the end-of-period cash and cash equivalents from the Company's Consolidated Balance Sheets and the total cash, cash equivalents and restricted cash as presented in the accompanying Consolidated Statements of Cash Flows (in thousands).

	For the Year Ended December 31,
	2020		2019
Cash and cash equivalents	$	90,257	$	67,904
Restricted cash classified in (1):
Prepaid expenses and other current assets		395		1,250
Other assets		—		38
Cash, cash equivalents and restricted cash shown in statement of cash flows	$	90,652	$	69,192

(1) Restricted cash consists of collateral required for letters of credit and credit card processing outside of the U.S. The short-term or long-term classification regarding the collateral for the letters of credit is determined in accordance with the expiration of the underlying lease as the letters of credit are non-cancellable while the leases are in effect.

Summary of Stock-Based Compensation Expense Recorded in Expense Categories

Stock-based compensation expense was recorded in the following expense categories (in thousands):

	Years Ended December 31,
	2020		2019		2018
Cost of services and fulfillment	$	6,156	$	6,627	$	4,329
Selling and marketing		1,751		1,768		1,065
General and administrative		2,970		3,289		2,906
Total	$	10,877	$	11,684	$	8,300

Shares Subject to Employee Stock Purchase Plan Valuation Assumptions

Shares subject to the employee stock purchase plan were valued utilizing the Black-Scholes model using the following assumptions and had the following fair values (no options were granted in 2020, 2019, or 2018):

	Years Ended December 31,
	2020			2019			2018
Average risk-free interest rate		0.12	%		1.89	%		1.90	%
Expected dividend yield		0.0	%		0.0	%		1.9	%
Expected life	0.5 Years			0.5 Years			0.5 Years
Expected volatility		93	%		30	%		23	%
Weighted average fair value	$	14.57		$	8.29		$	9.13

Depreciation and Amortization of Property and Equipment, Useful Life

Forrester provides for depreciation and amortization of property and equipment, computed using the straight-line method, over their estimated useful lives of its assets as follows:

	Estimated
	Useful Life
Computers and equipment	3 to 10 Years
Computer software	3 to 5 Years
Furniture and fixtures	7 Years
Leasehold improvements	Shorter of asset life or lease term

Amortization of Intangible Assets, Estimated Useful Life

Forrester provides for amortization of intangible assets, computed using an accelerated method according to the expected cash flows to be received from the underlying assets, over their estimated useful lives as follows:

	Estimated
	Useful Life
Customer relationships	5 to 9 Years
Technology	1 to 8 Years
Backlog	2 Years
Trademarks	7 to 9 Years

Schedule of Basic and Diluted Weighted Average Common Shares

Basic and diluted weighted average common shares are as follows (in thousands):

	Years Ended December 31,
	2020		2019		2018
Basic weighted average common shares outstanding		18,827		18,492		18,091
Weighted average common equivalent shares		108		—		289
Diluted weighted average common shares outstanding		18,935		18,492		18,380
Options and restricted stock units excluded from diluted weighted    average share calculation as effect would have been anti-dilutive		326		1,099		8