Organization and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Allowance for Credit Losses on Financing Receivables

The table below sets forth the components of the Allowance for Doubtful Accounts for the years ended December 31.

Year	Balance at January 1		Provision charged to expense		Write-offs / Recoveries			Balance at December 31
2014	$	1,189	$	1,099	$	(366	)	$	1,922
2015	$	1,922	$	—	$	(150	)	$	1,772
2016	$	1,772	$	172	$	(375	)	$	1,569

Schedule of Excess and Obsolete Inventory Reserve

The table below sets forth the components of the Excess and Obsolete Inventory Reserve for the years ended December 31.

Year	Balance at January 1		Provision charged to expense		Write-offs / Recoveries		Balance at December 31
2016	$	—	$	825	$	—	$	825

Schedule of Accumulated Other Comprehensive Income (Loss)

The changes in accumulated other comprehensive (loss) by component were as follows:

	December 31,
	2016			2015
Foreign currency translation
Balance at beginning of period	$	(1,568	)	$	(471	)
Other comprehensive (loss):
Foreign currency translation adjustments (1)	(6		)	(1,097		)
Balance at end of period	$	(1,574	)	$	(1,568	)
Available-for-sale marketable securities
Balance at beginning of period	$	12		$	23
Other comprehensive (loss):
Net unrealized holding (loss) (2)	(6		)	(11		)
Balance at end of period	$	6		$	12
Total accumulated other comprehensive (loss)	$	(1,568	)	$	(1,556	)

(1) In all periods presented, there were no tax impacts related to rate changes and no amounts were reclassified to earnings.

(2) In all periods presented, there were no realized holding gains or losses and therefore no amounts were reclassified to earnings.

Schedule of Goodwill

The following table shows our goodwill activity by reporting unit during the periods ending December 31, 2016 and 2015:

	2016
Reporting Unit	Beginning Carrying Amount		Acquired Goodwill		Impairment Charge			Ending Carrying Amount
FUEL CHEM Technology Segment	$	2,116	$	—	$	—		$	2,116
APC Technology Segment	—		—		—			—
	$	2,116	$	—	$	—		$	2,116
	2015
Reporting Unit	Beginning Carrying Amount		Acquired Goodwill		Impairment Charge			Ending Carrying Amount
FUEL CHEM Technology Segment	$	2,116	$	—	$	—		$	2,116
APC Technology Segment	—		—		—			—
	$	2,116	$	—	$	—		$	2,116
	2014
Reporting Unit	Beginning Carrying Amount		Acquired Goodwill		Impairment Charge			Ending Carrying Amount
FUEL CHEM Technology Segment	$	2,116	$	—	$	—		$	2,116
APC Technology Segment	18,935		4,465		(23,400		)	—
	$	21,051	$	4,465	$	(23,400	)	$	2,116

Schedule of Finite-Lived Intangible Assets

The table below shows the amortization period and other intangible asset cost by intangible asset as of December 31, 2016 and 2015, and the accumulated amortization and net intangible asset value in total for all other intangible assets.

		2016							2015
Description of Other Intangibles	Amortization Period	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Customer relationships	11-15 years	$	3,119	$	(2,979	)	$	140	$	3,633	$	(3,114	)	$	519
Trademarks and trade names	8 years	351		(351		)	—		441		(382		)	59
Patent assets	1- 20 years	3,100		(1,444		)	1,656		3,007		(1,210		)	1,797
Acquired technologies	5-8 years	4,138		(2,483		)	1,655		7,515		(2,746		)	4,769
Total		$	10,708	$	(7,257	)	$	3,451	$	14,596	$	(7,452	)	$	7,144

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

The table below shows the estimated future amortization expense for intangible assets:

Year	Estimated Amortization Expense
2017	$	805
2018	785
2019	574
2020	123
2021	123
Thereafter	1,041
Total	$	3,451

Property, Plant and Equipment

The table below shows the depreciable life and cost by asset class as of December 31, 2016 and 2015, and the accumulated depreciation and net book value in total for all classes of assets.

Description of Property and Equipment	Depreciable Life	2016			2015
Land		$	1,440		$	1,440
Building	39 years	4,535			4,535
Building and leasehold improvements	3-39 years	5,087			5,102
Field equipment	3-4 years	19,870			19,797
Computer equipment and software	2-3 years	2,973			2,978
Furniture and fixtures	3-10 years	1,521			1,527
Vehicles	5 years	36			36
Total cost		35,462			35,415
Less accumulated depreciation		(24,542		)	(23,414		)
Total net book value		$	10,920		$	12,001

Schedule of Earnings Per Share, Basic and Diluted

The table below sets forth the weighted-average shares used at December 31 in calculating earnings (loss) per share:

	2016	2015	2014
Basic weighted-average shares	23,365,000	23,101,000	22,782,000
Conversion of unsecured loan notes	—	—	—
Unexercised options and unvested restricted stock units	—	—	—
Diluted weighted-average shares	23,365,000	23,101,000	22,782,000