Ameresco, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Cover Page
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details
Uncategorized
- Uncategorized Items - amrc-20200930.htm

Earnings Per Share and Other Equity Related Information - Additional Information (Details)

v3.20.2

Earnings Per Share and Other Equity Related Information - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	May 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Aug. 31, 2019	Feb. 28, 2017	Apr. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock-based compensation expense		$ 521,000	$ 413,000	$ 1,380,000	$ 1,195,000
Treasury Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Open market purchase of common shares (in shares)			10,000	455	10,000
Class A Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock repurchase program, authorized amount (up to)						$ 17,553,000	$ 15,000,000	$ 10,000,000
Class A Common Stock \| 2020 Stock Incentive Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares reserved for future issuance (in shares)	5,000,000
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Non-vested stock options unrecognized compensation expense		$ 11,970,000		$ 11,970,000
Non-vested stock options unrecognized compensation expense, weighted-average period of recognition				2 years 7 months 6 days
Options granted in period (in shares)		95,000		376,000
Stock options, contractual period				10 years
Stock options, vesting period		5 years		5 years
Stock Options \| 2017 Employee Stock Purchase Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of allocated shares (up to) (in shares)	350,000
Discount from fair value of stock (as a percent)	5.00%
Stock issued during period (in shares)				28,000	22,000

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