Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

The components of stock-based compensation for the three and six months ended June 30, 2018 and 2017 were as follows:

	Three Months Ended   June 30,				Six Months Ended   June 30,
	2018		2017		2018		2017
Stock options and restricted stock units, net of forfeited	$	97	$	1,166	$	38	$	1,156
Tax benefit of stock-based compensation expense	—		—		—		—
After-tax effect of stock-based compensation	$	97	$	1,166	$	38	$	1,156

Schedule of Stock Option Activity

Stock option activity for Fuel Tech’s Incentive Plans for the six months ended June 30, 2018 was as follows:

	Number of Options		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding on January 1, 2018	1,116,750		$	6.34
Granted	—		—
Exercised	—		—
Expired or forfeited	(147,750	)	15.16
Outstanding on June 30, 2018	969,000		$	4.99	4.99	$	20,240
Exercisable on June 30, 2018	969,000		$	4.99	4.99	$	20,240

Schedule of Nonvested Restricted Stock Units Activity

A summary of restricted stock unit activity for the six months ended June 30, 2018 is as follows:

	Shares		Weighted Average Grant Date Fair Value
Unvested restricted stock units at January 1, 2018	1,359,162		$	1.28
Granted	—		—
Forfeited	(199,995	)	1.59
Vested	(48,890	)	1.59
Unvested restricted stock units at June 30, 2018	1,110,277		$	1.21