Arq (ARQ) 10-K 13 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 08, 2017	Jun. 30, 2016
Document Documentand Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Entity Registrant Name	Advanced Emissions Solutions, Inc.
Entity Central Index Key	1,515,156
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	No
Entity Voluntary Filers	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		22,022,683
Entity Public Float			$ 106.1

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
ASSETS
Cash and cash equivalents	$ 13,208	$ 9,265
Restricted cash	13,736	728
Receivables, net	8,648	8,361
Receivables, related parties, net	1,934	1,918
Costs in excess of billings on uncompleted contracts	25	2,137
Prepaid expenses and other assets	1,357	2,306
Total current assets	38,908	24,715
Restricted cash, long-term	0	10,980
Property and equipment, net of accumulated depreciation of $2,920 and $4,557	735	2,040
Investment securities, restricted, long-term	0	336
Cost method investment	1,016	2,776
Equity method investments	3,959	17,232
Deferred tax assets	61,396	0
Other assets	1,282	2,696
Total Assets	107,296	60,775
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Accounts payable	1,920	6,174
Accrued payroll and related liabilities	2,121	5,800
Current portion of notes payable, related parties	0	1,837
Billings in excess of costs on uncompleted contracts	4,947	9,708
Short-term borrowings, net of discount and deferred loan costs, related party	0	12,676
Legal settlements and accruals	10,706	6,502
Other current liabilities	4,017	7,395
Total current liabilities	23,711	50,092
Long-term portion of notes payable, related parties	0	13,512
Legal settlements and accruals, long-term	5,382	13,797
Other long-term liabilities	2,038	8,352
Total Liabilities	31,131	85,753
Commitments and contingencies (Note 14)	0	0
Stockholders’ equity (deficit):
Preferred stock: par value of $.001 per share, 50,000,000 shares authorized, none outstanding	0	0
Common stock: par value of $.001 per share, 100,000,000 shares authorized, 22,322,022 and 21,943,872 shares issued and 22,024,675 and 21,809,164 shares outstanding at December 31, 2016 and 2015, respectively	22	22
Additional paid-in capital	119,494	116,029
Accumulated deficit	(43,351)	(141,029)
Total stockholders’ equity (deficit)	76,165	(24,978)
Total Liabilities and Stockholders’ Equity (Deficit)	$ 107,296	$ 60,775

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Accumulated depreciation and amortization	$ 2,920	$ 4,557
Preferred stock par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	22,322,022	21,943,872
Common stock, shares outstanding (in shares)	22,024,675	21,809,164

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues:
Equipment sales	$ 46,949	$ 60,099	$ 12,044
Chemicals	3,025	888	391
Consulting services and other	648	1,752	4,488
Total revenues	50,622	62,739	16,923
Operating expenses:
Equipment sales cost of revenue, exclusive of depreciation and amortization	37,741	45,433	9,277
Chemicals cost of revenue, exclusive of depreciation and amortization	1,700	601	140
Consulting services and other cost of revenue, exclusive of depreciation and amortization	376	1,518	2,203
Payroll and benefits	12,390	23,589	20,767
Rent and occupancy	2,168	3,309	2,468
Legal and professional fees	8,293	16,604	14,430
General and administrative	3,721	6,104	6,066
Research and development, net	(648)	5,362	1,521
Depreciation and amortization	979	2,019	1,865
Total operating expenses	66,720	104,539	58,737
Operating loss	(16,098)	(41,800)	(41,814)
Other income (expense):
Earnings from equity method investments	45,584	8,921	42,712
Royalties, related party	6,125	10,642	6,410
Interest income	268	24	74
Interest expense	(5,066)	(8,402)	(5,725)
Litigation settlement and royalty indemnity expense, net	3,464	0	0
Other	2,463	494	26
Total other income	52,838	11,679	43,497
Income (loss) before income tax expense	36,740	(30,121)	1,683
Income tax (benefit) expense	(60,938)	20	296
Net income (loss)	$ 97,678	$ (30,141)	$ 1,387
Earnings (loss) per common share:
Basic (in dollars per share)	$ 4.40	$ (1.37)	$ 0.06
Diluted (in dollars per share)	$ 4.34	$ (1.37)	$ 0.06
Weighted-average number of common shares outstanding:
Basic (in shares)	21,931	21,773	21,554
Diluted (in shares)	22,234	21,773	22,079

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders’ Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit
Beginning Balances (in shares) at Dec. 31, 2013		21,661,908
Beginning Balances at Dec. 31, 2013	$ (6,167)	$ 22	$ 106,086	$ (112,275)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation (in shares)		40,729
Stock-based compensation	4,712		4,712
Issuance of stock to 401(k) plan (in shares)		5,250
Issuance of stock to 401(k) plan	127		127
Issuance of stock upon exercise of options, net (in shares)		260,126
Issuance of stock upon exercise of options, net	243		243
Repurchase of shares to satisfy tax withholdings (in shares)		(114,750)
Repurchase of shares to satisfy tax withholdings	(1,500)		(1,500)
Reclassification and settlement of equity awards	501		501
Net income (loss)	1,387			1,387
Ending Balances (in shares) at Dec. 31, 2014		21,853,263
Ending Balances at Dec. 31, 2014	(697)	$ 22	110,169	(110,888)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation (in shares)		127,867
Stock-based compensation	6,462		6,462
Clawback of equity awards (in shares)		(20,656)
Clawback of equity awards	(325)		(325)
Repurchase of shares to satisfy tax withholdings (in shares)		(16,602)
Repurchase of shares to satisfy tax withholdings	(277)		(277)
Net income (loss)	(30,141)			(30,141)
Ending Balances (in shares) at Dec. 31, 2015		21,943,872
Ending Balances at Dec. 31, 2015	(24,978)	$ 22	116,029	(141,029)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation (in shares)		405,354
Stock-based compensation	2,762		2,762
Repurchase of shares to satisfy tax withholdings (in shares)		(27,204)
Repurchase of shares to satisfy tax withholdings	(196)		(196)
Reclassification and settlement of equity awards	899		899
Net income (loss)	97,678			97,678
Ending Balances (in shares) at Dec. 31, 2016		22,322,022
Ending Balances at Dec. 31, 2016	$ 76,165	$ 22	$ 119,494	$ (43,351)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities
Net income (loss)	$ 97,678	$ (30,141)	$ 1,387
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Deferred tax benefit	(61,396)	0	0
Depreciation and amortization	979	2,019	1,865
Amortization of debt issuance costs	1,152	987	100
Debt prepayment penalty	228	0	0
Impairment of property, equipment, inventory and intangibles	520	2,087	355
Provision for bad debt expense and note receivable	13	633	500
Interest costs added to principal balance of notes payable	0	923	1,124
Consulting expense financed through note payable	0	0	1,600
Share-based compensation expense	2,868	7,204	4,712
Clawback of equity awards	0	(325)	0
Earnings from equity method investments	(45,584)	(8,921)	(42,712)
Gain on sale of equity method investment	(2,078)	0	0
Impairment of cost method investment	1,760	0	0
Gain on settlement of note payable, licensed technology, and sales-type lease	(1,910)	0	0
Other non-cash items, net	35	285	39
Changes in operating assets and liabilities, net of effects of acquired businesses:
Receivables	(301)	8,361	(3,651)
Related party receivables	(16)	(479)	(809)
Prepaid expenses and other assets	1,195	(107)	(1,877)
Costs incurred on uncompleted contracts	29,623	6,492	(56,606)
Other long-term assets	961	205	(47)
Accounts payable	(4,254)	(1,340)	2,328
Accrued payroll and related liabilities	(2,887)	(102)	686
Other current liabilities	(3,105)	(812)	(672)
Billings on uncompleted contracts	(32,272)	(15,186)	55,621
Advance deposit, related party	(2,980)	(3,544)	(2,135)
Other long-term liabilities	(2,175)	595	144
Legal settlements and accruals	(4,211)	(3,722)	(4,622)
Distributions from equity method investees, return on investment	7,900	5,019	2,509
Net cash used in operating activities	(18,257)	(29,869)	(40,161)
Cash flows from investing activities
Distributions from equity method investees in excess of cumulative earnings	38,250	8,651	43,584
Purchase of investment securities	0	0	(105)
Maturity of investment securities	0	0	210
Maturity of investment securities, restricted	336	0	403
Acquisition of property and equipment	(289)	(507)	(1,563)
Proceeds from sale of property and equipment	52	942	26
Advance on note receivable	0	(500)	(500)
Acquisition of business	0	(2,124)	0
Purchase of cost method investment	0	0	(2,776)
Purchase of and contributions to equity method investee	(223)	(2,128)	(6,631)
Proceeds from sale of equity method investment	1,773	0	0
Net cash provided by investing activities	39,899	4,334	32,648
Cash flows from financing activities
Short-term borrowings	0	13,539	0
Repayments on short-term borrowings	(13,250)	(1,750)	0
Repayments on notes payable, related party	(1,246)	(1,484)	(238)
Loan costs and amendment fees	(751)	0	(70)
Debt prepayment penalty	(228)	0	0
Proceeds received upon exercise of stock options	0	0	243
Repurchase of shares to satisfy tax withholdings	(196)	(276)	(1,500)
Net cash (used in) provided by financing activities	(15,671)	10,029	(1,565)
Increase (Decrease) in Cash and Cash Equivalents and Restricted Cash	5,971	(15,506)	(9,078)
Cash and Cash Equivalents and Restricted Cash, beginning of year	20,973	36,479	45,557
Cash and Cash Equivalents and Restricted Cash, end of year	26,944	20,973	36,479
Supplemental disclosure of cash flow information:
Cash paid for interest	3,647	6,274	5,201
Cash paid for income taxes	541	29	566
Supplemental disclosure of non-cash investing and financing activities:
Acquisition of technology license through long-term payable	0	0	1,525
Acquisition of equity method investment through note payable	0	0	13,301
Settlement of RCM6 note payable	13,234	0	0
Non-cash reduction of equity method investment	11,156	0	0
Stock award reclassification (liability to equity)	899	0	501
Issuance of common stock to settle liabilities	$ 0	$ 0	$ 127

Summary of Operations and Signi

Summary of Operations and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Operations and Significant Accounting Policies	Summary of Operations and Significant Accounting Policies Nature of Operations Advanced Emissions Solutions, Inc. ("ADES" or the "Company") is a Delaware corporation with its principal office located in Highlands Ranch, Colorado. The Company is principally engaged in providing environmental and emissions control equipment, technologies and specialty chemicals to the coal-burning electric power generation industry. The Company generates substantial earnings and tax credits under Section 45 of the Internal Revenue Code ("IRC") from its equity investments in certain entities and royalty payment streams related to technologies that are licensed to Tinuum Group, LLC, a Colorado limited liability company ("Tinuum Group") (f/k/a Clean Coal Solutions, LLC). Such technologies allow Tinuum Group to provide their customers with various solutions to enhance combustion and reduced emissions of nitrogen oxide ("NO x ") and mercury from coal burned to generate electrical power. The Company’s sales occur principally throughout the United States. See Note 17 for additional information regarding the Company's operating segments. As of December 31, 2016 , ADES's wholly-owned subsidiaries included: • ADA-ES, Inc. ("ADA"), a Colorado corporation • BCSI, LLC ("BCSI"), a Delaware limited liability company; • Advanced Clean Energy Solutions, LLC ("ACES"), a Delaware limited liability company; • ADEquity, LLC ("ADEquity"), a Delaware limited liability company; • ADA Environmental Solutions, LLC (“ADA LLC”), a Colorado limited liability company; • ADA-ES Intellectual Property, LLC (“ADA IP”), a Colorado limited liability company; • ADA Analytics, LLC, a Delaware limited liability company; • ADA Analytics Israel Ltd., an Israel limited liability company (collectively with ADA Analytics, LLC, "ADA Analytics"), which had no operations for the years ended December 31, 2016 and December 31, 2015 ADA LLC ceased operations in 2012 and ADA IP has had no operations since inception. During 2015, the Company elected to cease the operations of ADA Analytics. The Company anticipates that ADA Analytics will be legally dissolved during 2017. In addition, the Company terminated its manufacturing operations, conducted under BCSI, effective as of the end of the 2015. The Company anticipates that BCSI will eventually be legally dissolved upon the winding down of its remaining operations, commitments and obligations. However, the Company has continued to serve the Dry Sorbent Injection ("DSI") market, which BCSI previously served, through ADA. In addition, we are an investor in Tinuum Group and Tinuum Services, LLC ("Tinuum Services") (f/k/a Clean Coal Solutions Services, LLC), which are accounted for using the equity method of accounting and whose results significantly impact our financial position and results of operations. As of December 31, 2016 , the Company holds equity interests of 42.50% and 50.00% in Tinuum Group and Tinuum Services, respectively. As discussed in Note 7 , the Company sold its equity investment in RCM6, LLC ("RCM6") in March 2016, which was also accounted for using the equity method prior to the sale. Principles of Consolidation The Consolidated Financial Statements include accounts of wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. All investments in partially owned entities for which the Company has greater-than-20% ownership are accounted for using the equity method based on the legal form of the Company's ownership percentage and the applicable ownership percentage of the entity and are included in the Equity method investments line item in the Consolidated Balance Sheets . Tinuum Group is deemed to be variable interest entity ("VIE") under the VIE model of consolidation, but the Company does not consolidate Tinuum Group as it is not deemed to be its primary beneficiary. Cash and Cash Equivalents Cash and cash equivalents include bank deposits and other highly liquid investments purchased with an original maturity of three months or less. Restricted Cash Restricted cash primarily consists of funds withheld to provide collateral support for certain letters of credit issued to i) customers related to certain contractual performance and payment guarantees, ii) certain settlement parties to provide security for continuing royalty indemnification payments related to the settlement of certain litigation (the "Royalty Award"), and iii) minimum cash balance requirements under the 2013 Loan and Security Agreement ("Line of Credit"). Receivables and Credit Policies Receivable balances represent unsecured, customer obligations due under trade terms typically requiring payment within 30 - 45 days from the invoice date and are stated net of allowance for doubtful accounts. The Company records allowances for doubtful accounts when it is probable that the accounts receivable balances will not be collected. The following tables show the receivables balances: As of December 31, (in thousands) 2016 2015 Receivables $ 4,289 $ 8,518 Other Receivables 4,559 — Less: Allowance for doubtful accounts (200 ) (157 ) Total $ 8,648 $ 8,361 As of December 31, (in thousands) 2016 2015 Receivables, related parties $ 1,934 $ 1,918 Total $ 1,934 $ 1,918 During the years ended December 31, 2016 , 2015 and 2014 , the Company recognized zero , $0.1 million and zero , respectively, of bad debt expense related to the write-off of specific accounts whose ultimate collection was in doubt. Bad debt expense is included within the General and administrative line item in the Consolidated Statements of Operations . Notes receivable are reported at their outstanding principal balances, adjusted for any amounts determined to be uncollectible. During the years ended December 31, 2015 and 2014 , the Company recorded impairment charges related to a Note Receivable of $0.5 million and $0.5 million , respectively, related to the write-off of a specific account whose ultimate collection was in doubt. Interest income is accrued and credited to income based on the unpaid principal balance outstanding. The accrual of interest is discontinued when substantial doubt exists about the ability to collect principal and interest based upon the contractual terms. Notes receivable are included within the Other assets line item in the Consolidated Balance Sheets . Additional details regarding Note receivable balances are included in Note 11 . Inventory Inventories are stated at the lower of cost or market and consist principally of parts, components and materials for activated carbon injection ("ACI") and dry sorbent injection ("DSI") projects. The cost of inventory is determined using the first-in-first-out ("FIFO") method. Inventories are included within the Other assets line item in the Consolidated Balance Sheets . As of December 31, 2016 and 2015 , the balance of inventory was comprised of materials and supplies and finished goods of zero and $0.2 million , respectively. Other Intangible Assets Other Intangible assets consist of patents and licensed technology and are included in the Other assets line item in the Consolidated Balance Sheets . During the year ended December 31, 2016 , the Company entered into an agreement with Highview Enterprises Limited ("Highview") to terminate a license agreement (the "License Agreement") to certain technology ("Licensed Technology") in exchange for a one-time payment by the Company of £0.2 million (approximately $0.2 million ). Under the termination, payment of the termination fee, if any, will only be settled by relinquishing shares of Highview currently owned by the Company equal to £0.2 million . As a result of terminating the License Agreement, the Company wrote off the Licensed Technology, reduced the corresponding long-term liability ("Highview Obligation") to the amount of the one-time payment, and recognized a gain of approximately $0.2 million . The gain on the settlement of the Highview Obligation is included in the Other income line on the Company's Consolidated Statement of Operations for the year ended December 31, 2016. During the years ended December 31, 2015 and 2014 , the Company did not recognize any intangible asset impairment charges. The Company has developed technologies resulting in patents being granted by the U.S. Patent and Trademark Office. All research and development costs associated with the technology development are expensed as incurred. Legal costs associated with securing the patent are capitalized and amortized over the legal or useful life beginning on the patent filing date. Years Ended December 31, 2016 2015 (in thousands, except years) Weighted-Average Amortization Period (in years) Initial Cost Net of Accumulated Amortization Initial Cost Net of Accumulated Amortization Patents 16 $ 913 $ 696 $ 742 $ 581 Licensed technology 0 1,525 — 1,525 1,360 Total 16 $ 2,438 $ 696 $ 2,267 $ 1,941 Included in the Consolidated Statements of Operations is amortization expense related to intangible assets of $0.1 million , $0.4 million and zero for the years ended December 31, 2016 , 2015 and 2014 , respectively. The estimated future amortization expense for existing intangible assets as of December 31, 2016 is expected to be $0.1 million for each of the five succeeding fiscal years. Investment Securities Investment securities represent certificates of deposits with original maturities greater than 90 days. Investment securities pledged as security for letters of credit in the same amount as the investments are classified as restricted in the accompanying Consolidated Balance Sheets and are carried at fair value. Investments in partially-owned subsidiaries for which the Company has less-than-20% ownership are accounted for using the cost method. Cost method investments are evaluated for impairment upon an indicator of impairment such as an event or change in circumstances that may have a significant adverse effect on the fair value of the investment. If no such events or changes in circumstances have occurred, the fair value is estimated only if practicable to do so. Equity Method of Accounting The investments in entities in which the Company does not have a controlling interest (financial or operating), but where it has the ability to exercise significant influence over operating and financial policies, are accounted for using equity-method accounting. Whether or not the Company exercises significant influence with respect to an investee depends on an evaluation of several factors including, among others, representation on the investee company’s board of directors and the Company's ownership level. Under the equity method of accounting, an investee company’s accounts are not reflected within the Company’s Consolidated Balance Sheets and Consolidated Statements of Operations ; however, the Company’s share of the earnings or losses of the investee company is reported in the Earnings from equity method investments line item in the Consolidated Statements of Operations and the Company’s carrying value in an equity method investee company is reported in the Equity method investments line in the Consolidated Balance Sheets . When the Company receives distributions in excess of the carrying value of the investment and the Company has not guaranteed any obligations of the investee, nor is it required to provide additional funding to the investee, the Company recognizes such excess distributions as equity method earnings in the period the distributions occur. When the investee subsequently reports income, the Company does not record its share of such income until it equals the amount of distributions in excess of carrying value that were previously recognized in income. During the years ended December 31, 2016 , 2015 and 2014 , the Company had no guarantees or requirements to provide additional funding to investees. Additionally, when the Company's carrying value in an equity method investment is zero and the Company has not guaranteed any obligations of the investee, nor is it required to provide additional funding to the investee, the Company will not recognize its share of any reported losses by the investee until future earnings are generated to offset previously unrecognized losses. As a result, equity income or loss reported on the Company's Consolidated Statements of Operations for certain equity method investment entities may differ from a mathematical calculation of net income or loss attributable to its equity interest based upon the percentage ownership of our equity interest and the net income or loss attributable to equity owners as shown on investee companies' statements of operations. Likewise, distributions from equity method investees are reported on the Consolidated Statements of Cash Flows as “return on investment” within Operating cash flows until such time as the carrying value in an equity method investee company is reduced to zero; thereafter, such distributions are reported as “distributions in excess of cumulative earnings” within Investing cash flows. See Note 7 for additional information regarding the Company's equity method investments. Royalties, Related Party The Company licenses its M-45 TM and M-45-PC TM emission control technologies ("M-45 License") to Tinuum Group and realizes royalty income based upon (i) a percentage of the per-ton, pre-tax margin net of certain allocable operating expenses related to the lease or sale of an invested RC Facility that produces and sells RC under the M-45 License, (ii) a percentage of the value of the Section 45 tax credits generated related to retained RC facilities, net of certain allocable operating expenses as a result of the production and sale of RC under the M-45 License, and (iii) a percentage of the revenue, net of all direct expenses, received by Tinuum Group as a direct result of Tinuum Group's exercise of the M-45 License. Property and Equipment Property and equipment is stated at cost less accumulated depreciation and includes leasehold improvements. Depreciation on assets is computed using the straight-line method over the lesser of the estimated useful lives of the related assets or the lease term (ranging from 2 to 7 years). Maintenance and repairs which do not extend the useful life of the respective asset are charged to Operating expenses as incurred. When assets are retired, or otherwise disposed of, the property accounts are relieved of costs and accumulated depreciation and any resulting gain or loss is credited or charged to income. The Company performs an evaluation of the recoverability of the carrying value of its long-lived assets to determine if facts and circumstances indicate that the carrying value of assets may be impaired and if any adjustment is warranted. Revenue Recognition The Company recognizes revenues when: (i) persuasive evidence of a customer arrangement exists; (ii) the price is fixed or determinable; (iii) collectability is reasonable assured; and (iv) product delivery has occurred or services have been rendered and it is probable that performance guarantees, if any, will be met. Equipment sales The Company enters into contracts that require, over a period of months, the design and construction of emissions control systems ("extended equipment contracts"). Revenues from such extended equipment contracts are recorded using the percentage of completion cost to cost method based on costs incurred to date compared with total estimated contract costs. However, if the Company does not have sufficient information to estimate either costs incurred or total estimated costs for extended equipment contracts, the completed contract method is used. Under the completed contract method, revenues and costs from extended equipment contracts are deferred and recognized when contract obligations are substantially complete. The Company defines substantially complete as delivery of equipment and start-up at the customer site or, as applicable to DSI systems, the completion of any major warranty service period. Such costs are accumulated in the Costs in excess of billings on uncompleted contracts or Billings in excess of costs on uncompleted contracts line items in the Consolidated Balance Sheets , and typically include direct materials, direct labor and subcontractor costs, and indirect costs related to contract performance, such as indirect labor, supplies, tools and repairs. For each of the years ended December 31, 2016 , 2015 and 2014 , the Company did not have sufficient information to measure ongoing performance for its extended equipment contracts. Accordingly, the completed contract method of revenue recognition has been used for each of these years, and revenues and costs are deferred until the equipment is placed into service and contract obligations are substantially complete. When multiple contracts exist with a single counterparty, the Company evaluates revenue recognition on a contract-by-contract basis. Provisions for estimated losses on uncompleted contracts are recognized when it has been determined that a loss is probable. The Company also enters into other non-extended equipment contracts for which the Company recognizes revenues on a time and material basis as services to build equipment systems are performed or as equipment is delivered. Chemicals Revenues for direct sales of chemicals and other ancillary products not provided in the performance of construction of emissions control systems (extended equipment sales) are recognized at the date of delivery to, and acceptance by, the customer. Consulting services and other The Company recognizes revenues on time and material contracts as services are performed. Cost of Revenue Costs of revenue include all labor, fringe benefits, subcontract labor, chemical and coal costs, materials, equipment, supplies, travel costs and any other costs and expenses directly related to the Company’s production of revenues. The Company records estimated contract losses, if any, in the period they are determined. Warranty costs for ACI equipment systems are estimated based on historical experience and are recorded as a percentage of revenue when the equipment is substantially complete. Warranty costs, comprised of the cost of replacement materials and direct labor, are included within the Equipment sales cost of revenue line in the Consolidated Statements of Operations . Warranty costs for DSI equipment systems could not be estimated at the time the contracts were entered into due to a lack of historical experience manufacturing DSI systems and the resulting claims history, if any, needed to determine an appropriate warranty amount. Therefore, revenue recognition on DSI equipment systems is deferred until the end of the warranty period, which is generally 12 to 24 months following substantial completion. As warranty claims are incurred, such costs are deferred within the Costs in excess of billings on uncompleted contracts line item in the Consolidated Balance Sheets , until such time that revenues and cost of revenue are recognized. Subsequent to revenues being recognized, warranty claims are included within the Other long-term liabilities line item in the Consolidated Balance Sheets and within Cost of revenue line of the Consolidated Statements of Operations . The changes in the carrying amount of the Company’s warranty obligations, which do not include amounts for DSI systems as revenues are deferred until the end of the warranty period, are included in Note 11 . In some cases, a letter of credit is obtained and held to cover the period of the warranty that could be used to satisfy the obligation. Payroll and Benefits Payroll and benefits costs include direct payroll, personnel related fringe benefits, sales and administrative staff labor costs and stock compensation expense. Payroll and benefits costs exclude direct labor included in Cost of revenue. Rent and Occupancy Rent and occupancy costs include rent, insurance and other occupancy-related expenses. Legal and Professional Legal and professional costs include external legal, audit and consulting expenses. General and Administrative General and administrative costs include director fees and expenses, bad debt expense, impairments and other general costs of conducting business. Research and Development Costs Research and development costs are charged to expense in the period incurred. The Company has entered into development and cost-sharing contracts with the U.S. Department of Energy (the "DOE"). These contracts are best-effort-basis contracts, and the Company generally includes industry cost-share partners to offset the costs incurred that are anticipated to be in excess of funded amounts from the DOE. The Company accounts for these contracts with the DOE and industry cost-share partners in accordance with accounting guidance whereby the Company recognizes amounts funded by the DOE under research-and-development-cost-sharing arrangements as an offset to the Company's aggregate research and development expense reported in the Research and development, net line in the Consolidated Statements of Operations . Asset Retirement Obligations The Company's asset retirement obligation, or "ARO liability," consists of estimated costs to remove equipment and reclaim the land associated with one research and development project. The Company estimates its ARO liability for final reclamation based upon bids obtained from independent third parties and other exit alternatives, which are adjusted for inflation, and then discounted at a credit-adjusted risk-free rate. Changes in estimates could occur due to revisions of estimated costs and changes in timing and performance of the reclamation activities. The ARO liability is included within the Other long-term liabilities line item in the Consolidated Balance Sheets and discussed further in Note 11 . Income Taxes The Company accounts for income taxes under the asset and liability method which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date. The Company recognizes deferred tax assets and liabilities and maintains valuation allowances where it is more likely than not that all or a portion of deferred tax assets will not be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. The Company records uncertain tax positions on the basis of a two-step process whereby (1) the Company determines whether it is more-likely-than-not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company records interest expense due to the Company's share of Tinuum Group's equity method earnings for Refined Coal ("RC") facility leases which are treated as installment sales for tax purposes. IRS section 453A requires taxpayers using the installment method to pay an interest charge on the portion of the tax liability that is deferred under the installment method. The Company recognizes IRS section 453A interest ("453A interest") and other interest and penalties related to unrecognized tax benefits in the Interest expense line item in the Consolidated Statements of Operations . Stock-Based Compensation Stock-based compensation expense is measured at the grant date based on the estimated fair value of the stock-based award and expensed on a straight-line basis over the requisite service period for the entire award. Forfeitures are recognized when incurred. These costs are recorded in the Payroll and benefits line item in the Consolidated Statements of Operations . Earnings (Loss) Per Share Basic earnings (loss) per share is computed using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for common stock and any participating securities according to dividend and participating rights in undistributed earnings. The Company's restricted stock awards ("RSA's") contain non-forfeitable rights to dividends or dividend equivalents and are deemed to be participating securities. The Company did not declare any cash dividends during the years ended December 31, 2016 , 2015 or 2014 . Under the two-class method, net income (loss) for the period is allocated between common stockholders and the holders of the participating securities based on the weighted-average of common shares outstanding during the period, excluding unvested RSA's ("common shares"), and the weighted-average number of unvested RSA's outstanding during the period, respectively. The allocated, undistributed income (loss) for the period is then divided by the weighted-average number of common shares and unvested RSA's outstanding during the period to arrive at basic earnings (loss) per common share and participating security for the period, respectively. Because the Company did not declare any dividends during the periods presented, and because the unvested RSA's possess substantially the same rights to undistributed earnings as common shares outstanding, there is no difference between the calculated basic earnings (loss) per share for common shares and participating securities. Accordingly, and pursuant to accounting principles generally accepted in the United States ("U.S. GAAP"), the Company has elected not to separately present basic or diluted earnings (loss) per share attributable to participating securities in the Consolidated Statements of Operations. Diluted earnings (loss) per share is computed in a manner consistent with that of basic earnings (loss) per shares, while considering other potentially dilutive securities. Potentially dilutive securities consist of outstanding options to purchase common stock and contingent performance stock units ("PSU's") (collectively, "Potential dilutive shares"), and their dilutive effect, if any, is computed using the treasury stock method. Potential dilutive shares are excluded from diluted earnings (loss) per share when their effect is anti-dilutive. When there is a net loss for a period, all Potential dilutive shares are anti-dilutive and are excluded from the calculation of diluted loss per share for that period. Each PSU represents a contingent right to receive shares of the Company’s common stock, and the number of shares may range from zero to two times the number of PSU's granted on the award date depending upon the price performance of the Company's common stock as measured against a general index and a specific peer group index over requisite performance periods. The number of Potential dilutive shares related to PSU's is based on the number of shares of the Company's common stock, if any, that would be issuable at the end of the respective reporting period, assuming that the end of the reporting period is the end of the contingency period applicable to such PSU's. See Note 13 for additional information related to PSU's. Potential dilutive shares were excluded in the diluted loss per share calculation for the year ended December 31, 2015 , as their inclusion was anti-dilutive due to the Company’s net loss for that year. The following table sets forth the calculations of basic and diluted earnings (loss) per common share: Years Ended December 31, (in thousands, except per share amounts) 2016 2015 2014 Net income (loss) $ 97,678 $ (30,141 ) $ 1,387 Less: Undistributed income (loss) allocated to participating securities 1,105 (275 ) 18 Income (loss) attributable to common stockholders $ 96,573 $ (29,866 ) $ 1,369 Basic weighted-average number of common shares outstanding 21,931 21,773 21,554 Add: dilutive effect of equity instruments 303 — 525 Diluted weighted-average number of common shares outstanding 22,234 21,773 22,079 Earnings (loss) per share - basic $ 4.40 $ (1.37 ) $ 0.06 Earnings (loss) per share - diluted $ 4.34 $ (1.37 ) $ 0.06 The table below presents the number of Potential dilutive shares that were excluded from the calculation of diluted loss per share because their inclusion would have been anti-dilutive: Years Ended December 31, (share data in thousands) 2016 2015 2014 Stock options — 10 — Restricted stock awards — 163 — Performance share units — 182 — Total shares excluded from diluted shares outstanding — 355 — Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. Actual results could differ from those estimates. The Company makes significant assumptions concerning: • revenue recognition, warranty estimates and performance guarantee accruals related to the Company's extended equipment contracts; • the impairment, or lack thereof, of the remaining realizability of, its long-lived assets; • stock compensation costs related to PSU and option awards; • estimated future royalty obligations associated with the Royalty Award and other legal accruals; and • the deferred tax assets expected to be realized in future periods and uncertain tax positions. Reclassifications Certain balances have been reclassified from prior years to conform to the current year presentation. New Accounting Guidance In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09"), which provides a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific guidance. The core principle of ASU 2014-09 is that “an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 becomes effective for reporting periods (including interim periods) beginning after December 31, 2017. Early application is permitted for annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The standard may be applied retrospectively to each prior period presented or retrospectively with the cumulative effect recognized as of the date of adoption ("modified retrospective method"). The Company anticipates adopting the standard under the modified retrospective method effective January 1, 2018, which will be reflected in its financial statements as of and for the three months ended March 31, 2018. Based on the Company's preliminary assessment of the standard, the Company has determined that the timing of revenue recognition for equipment sales may be impacted, but that revenues generated from chemical sales and consulting services will likely not be impacted. The Company is continuing its assessment, which may change its initial assessments of the impacts to its revenue streams or may identify other impacts. In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements - Going Concern (Topic 205-40), Disclosure of Uncertainties about an Entities Ability to Continue as a Going Concern that requires management to evaluate whether there are conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern within one year after the date that the entity’s financial statements are issued, or within one year after the date the entity’s financial statements are available to be issued, and to provide disclosures when certain criteria are met. This guidance is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The Company adopted this provision as of December 31, 2016 and there was no impact to the Company's financial statements or disclosures from the adoption of this

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring During the year ended December 31, 2016 , the Company recorded restructuring charges in connection with a reduction in force, the departure of certain executive officers and management's further alignment of the business with strategic objectives. These charges related to severance arrangements with departing employees and executives as well as non-cash charges related to the acceleration of vesting of certain stock awards. During the year ended December 31, 2015 , the Company recorded restructuring charges in connection with a reduction in force, the departure of executive officers and management's further alignment of the business with strategic objectives. These charges related to severance arrangements with departing employees and executives, including non-cash charges related to the acceleration of vesting of certain stock awards. In 2015 , the charges also related to the closing of the BCSI facilities and the termination of the operations of ADA Analytics, a foreign subsidiary that was involved in the development of certain data analytics and monitoring products. Furthermore, during the fourth quarter of 2015, the Company closed its fabrication facility in McKeesport, Pennsylvania and recorded restructuring charges related thereto. During the year ended December 31, 2014 , the Company recorded restructuring charges primarily related to a reduction in force, the departure of executive officers and management's alignment of the business with strategic objectives. These charges were related to severance agreements with departing employees and executives, including non-cash charges related to the acceleration of vesting of certain stock awards. A summary of the net pretax charges incurred by segment is as follows: Pretax Charge (in thousands, except employee data) Approximate Number of Employees Refined Coal Emissions Control All Other and Corporate Total Year ended December 31, 2016 Restructuring charges 40 $ — $ 1,164 $ 881 $ 2,045 Changes in estimates — (210 ) (276 ) (486 ) Total pretax charge, net of reversals $ — $ 954 $ 605 $ 1,559 Year ended December 31, 2015 Restructuring charges 162 $ — $ 5,108 $ 5,264 $ 10,372 Changes in estimates — (10 ) (2 ) (12 ) Total pretax charge, net of reversals $ — $ 5,098 $ 5,262 $ 10,360 Year ended December 31, 2014 Restructuring charges 29 $ — $ 1,294 $ 2,209 $ 3,503 Total pretax charge, net of reversals $ — $ 1,294 $ 2,209 $ 3,503 The following table summarizes the Company's utilization of restructuring accruals for the years ended December 31, 2016 , 2015 and 2014 : (in thousands) Employee Severance Facility Closures Beginning accrual as of January 1, 2014 $ 29 $ — Expense provision (1) 3,503 — Cash payments and other (1) (1,842 ) — Change in estimates (1) — — Accrual as of December 31, 2014 1,690 — Expense provision (1) 8,498 2,650 Cash payments and other (1) (7,595 ) (1,873 ) Change in estimates (1) (12 ) — Accrual as of December 31, 2015 2,581 777 Expense provision (1) 2,045 — Cash payments and other (1) (3,898 ) (320 ) Change in estimates (1) (276 ) (210 ) Accrual as of December 31, 2016 $ 452 $ 247 (1) Included within the Expense provision and Cash payments and other line items in the above table is equity-based compensation of $0.4 million , $3.4 million and $1.0 million for the years ended December 31, 2016 , 2015 and 2014 , respectively, resulting from the accelerated vesting of modified equity-based compensation awards for certain terminated employees. Additionally, as discussed in Note 8 , due to restructuring activities the Company fully impaired the carrying value of certain assets, thereby recognizing net impairment expense in the amount of $1.9 million during the year ended December 31, 2015 . Restructuring accruals related to personnel are included within the Accrued payroll and related liabilities line item in the Consolidated Balance Sheets . Restructuring expenses related to personnel are included within the Payroll and benefits and Research and development, net line items in the Consolidated Statements of Operations . Restructuring accruals related to facilities are included within the Other current liabilities line item in the Consolidated Balance Sheets . Restructuring expenses related to facilities are included within the Rent and occupancy line item in the Consolidated Statements of Operations .

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment The carrying basis and accumulated depreciation of property and equipment at December 31, 2016 and 2015 are: Life in Years As of December 31, (in thousands) 2016 2015 Machinery and equipment 2-7 $ 1,634 $ 3,498 Leasehold improvements 5-7 1,244 2,172 Furniture and fixtures 5-7 777 927 3,655 6,597 Less accumulated depreciation and amortization (2,920 ) (4,557 ) Total property and equipment, net $ 735 $ 2,040 Depreciation expense for the years ended December 31, 2016 , 2015 and 2014 was $0.9 million , $1.7 million and $1.8 million , respectively. During the year ended December 31, 2016 , the Company recorded impairments totaling approximately $0.5 million to reduce the carrying value of certain property and equipment that the Company intended to sell at its estimated sales value, less estimated costs to sell. The property and equipment was subsequently sold at auction. No gain or loss was recognized on the sale of the property and equipment. During the year ended December 31, 2016 , the Company accelerated depreciation of approximately $0.2 million related to property and equipment that will be no longer be in service due to the lease termination described in Note 14 . As discussed in Note 2 , as part of a broader strategic restructuring of the Company's business, the Company’s management approved an action to wind down the manufacturing operations of BCSI, LLC, in order to focus the Company's efforts within the DSI market on engineering. During 2015, the Company classified certain assets used in the BCSI, LLC manufacturing operations as held for sale. In doing so, the Company recognized impairment expense of approximately $0.3 million to reduce the carrying value of the assets to their estimated sales value, less estimated costs to sell. The property and equipment was subsequently sold at auction. Proceeds from the sale of the impaired assets totaled approximately $0.6 million . No gain or loss was recognized on the sale of the property and equipment. Also during 2015, the Company sold certain property and equipment having a net book value of approximately $0.1 million . Proceeds from the sale totaled approximately $0.3 million , which resulted in the recognition of a gain on the sale of approximately $0.2 million . The Company also closed its fabrication facility in McKeesport, Pennsylvania during 2015 and recognized $0.8 million of expense related to the abandonment of leased facilities.

Investments

Investments	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The Company did not have any investment securities related to certificates of deposit as of December 31, 2016 . The Company had investment securities related to certificates of deposit in the amount of $0.3 million as of December 31, 2015 . No unrealized gains or losses were recorded as of December 31, 2015 related to these investment securities. In November 2014, the Company acquired an 8% ownership interest in the common stock of Highview, a London, England based developmental stage company specializing in power storage, for $2.8 million in cash (the "Highview Investment"). The Company evaluated the Highview Investment and determined that it should account for it under the cost method. As of December 31, 2016 and December 31, 2015 , the Highview Investment was in the amount of $1.0 million and $2.8 million , respectively. No unrealized gains or losses were recorded as of December 31, 2016 and December 31, 2015 related to the Highview Investment. The Highview Investment is evaluated for impairment based on indicators of impairment such as an event or change in circumstances that may have a significant adverse effect on the fair value of the investment. When there are no indicators of impairment present, the Company estimates the fair value of the Highview Investment only if it is practical to do so. As of December 31, 2016 , the Company estimated the fair value of the Highview Investment based upon an anticipated equity raise by Highview at a price of £2.00 per share. As £2.00 per share is less than the Company's cost per share of £4.25 , the Company recorded an impairment charge of $1.8 million as of December 31, 2016 , which is included in Other line item in the Consolidated Statement of Operations. As of December 31, 2015 , there were no indicators of impairment, and the Company estimated that the fair value of the Highview Investment approximated the November 2014 purchase price due to the proximity of the purchase date to December 31, 2015 .

Costs and Billings on Uncomplet

Costs and Billings on Uncompleted Contracts	12 Months Ended
	Dec. 31, 2016
Costs and Billings on Uncompleted Contracts [Abstract]
Costs and Billings on Uncompleted Contracts	Costs and Billings on Uncompleted Contracts Costs incurred on uncompleted contracts represent the gross costs as of the balance sheet dates. Billings on uncompleted contracts represent the gross billings as of the balance sheet dates. Costs and billings are netted on an individual contract basis, with contracts in a net cost position aggregated and presented as Costs in excess of billings on uncompleted contracts in the Consolidated Balance Sheets , and contracts in a net billing position aggregated and presented as Billings in excess of costs on uncompleted contracts in the Consolidated Balance Sheets . The below table shows the components of these items: As of December 31, (in thousands) 2016 2015 Costs incurred on uncompleted contracts (gross) $ 42,993 $ 72,581 Billings on uncompleted contracts (gross) (47,915 ) (80,152 ) $ (4,922 ) $ (7,571 ) Included in the accompanying balance sheets under the following captions (1) : Costs in excess of billings on uncompleted contracts $ 25 $ 2,137 Billings in excess of costs on uncompleted contracts (4,947 ) (9,708 ) $ (4,922 ) $ (7,571 ) (1) Amounts presented after netting of costs and billings on an individual contract basis. When the Company determines that a contract will ultimately be completed at a loss, the Company estimates such loss and accrues the loss as a loss contract accrual in the period that the loss determination is made. Loss contract accruals of $0.2 million and $0.8 million as of December 31, 2016 and 2015 , respectively, are included in Other current liabilities line item in the Consolidated Balance Sheets . During the years ended December 31, 2016 , 2015 and 2014 , the Company recorded loss contract provisions of $0.4 million , $0.3 million and $0.3 million , respectively. Loss contract provisions are included within the Equipment sales cost of revenue, exclusive of depreciation and amortization line item in the Consolidated Statements of Operations .

Research and Development and Go

Research and Development and Government and Industry Funded Contracts	12 Months Ended
	Dec. 31, 2016
Government and Industry Funded Contracts [Abstract]
Research and Development and Government and Industry Funded Contracts	Research and Development and Government and Industry Funded Contracts The Company has invested directly in multiple emerging technologies, such as power generation data analytics, technologies aimed at the separation, capture and control of CO 2 emissions related to power generation, natural gas small scale liquefaction technologies and energy storage applications through and research and development activities supported by contracts with the DOE and industry participants. The contracts with the DOE can take the form of grants or cooperative agreements and are considered financial assistance awards. The deliverables required by the DOE agreements include various technical and financial reports that the Company submits on a prescribed schedule. The agreements require the Company to perform the negotiated scope of work in agreed phases, which includes testing and demonstration of technologies. The Company has participated in several contracts awarded by the DOE. The Company typically invoices the DOE and industry cost-share partners monthly for labor and expenditures plus estimated overhead factors, less any cost share amounts. The contracts under which the Company has performed are subject to audit, the result of which may require the Company to reimburse the DOE for disallowed costs and other adjustments. The Company has not experienced any material adverse adjustments as a result of completed government audits. However, the government audits for years ended 2010 through 2015 have not yet been finalized. The following table shows the impact to Research and development expense amounts recognized in the Consolidated Statement of Operations: Years Ended December 31, (in thousands) 2016 2015 2014 Research and development expense $ 173 $ 6,737 $ 3,554 Less: DOE funding 821 1,375 1,756 Industry cost-share funding — — 277 Research and development expense, net $ (648 ) $ 5,362 $ 1,521 Included within the above research and development expenses during 2015 is net impairment expense of $1.9 million for the entire carrying value of the Company's ADA Analytics' assets, as discussed in Note 2 and Note 8 .

Equity Method Investments

Equity Method Investments	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	Equity Method Investments Tinuum Group, LLC As of December 31, 2016 and 2015 , the Company’s ownership in Tinuum Group was 42.5% . Tinuum Group supplies technology, equipment and technical services to cyclone-fired and other boiler users, but its primary purpose is to put into operation facilities that produce and sell RC that lower emissions and therefore qualify for tax credits available under Section 45 of the IRC ("Section 45 tax credits"). NexGen Refined Coal, LLC ("NexGen") and GSFS Investments I Corp. (“GSFS”), an affiliate of The Goldman Sachs Group, Inc. ("GS"), own the remaining 42.5% and 15.0% , respectively of Tinuum Group. GSFS' ownership interest is in the form of Class B units which provide certain preferences over ADA and NexGen as to liquidation and profit distribution, including a guaranteed 15% annual return on GSFS' unrecovered investment balance, which is calculated as the original GSFS investment, plus a 15% annual return thereon, less any distributions, including the allocation of Section 45 tax credits to the members. Additionally, on the 10 year anniversary of the date the last RC facility owned by Tinuum Group or one of its subsidiaries is placed into service, but no later than December 31, 2021, if GSFS's unrecovered investment balance has not been reduced to zero, GSFS may require Tinuum Group to redeem its Class B units for an amount equal to the then unrecovered investment balance, payable within 180 days of the notice of redemption. GSFS has no further capital call requirements and does not have a voting interest, but does have approval rights over certain corporate transactions. However, the Class B units do not have voting rights and ADA and NexGen each maintain a 50% voting interest in Tinuum Group. Tinuum Group had been determined to be a VIE, however, the Company does not have the power to direct the activities that most significantly impact Tinuum Group's economic performance and has therefore accounted for the investment under the equity method of accounting. The Company determined the voting partners of Tinuum Group have identical voting rights, equity control interests and board control interests, and therefore, concluded that the power to direct the activities that most significantly impact Tinuum Group's economic performance was shared. The following tables summarize the assets, liabilities and results of operations of Tinuum Group: As of December 31, (in thousands) 2016 2015 Current assets $ 24,584 $ 40,860 Non-current assets $ 83,621 $ 90,725 Current liabilities $ 43,117 $ 60,987 Non-current liabilities $ 11,456 $ 9,412 Redeemable Class B equity $ 18,250 $ 30,448 Members deficit attributable to Class A members $ 26,475 $ 25,175 Noncontrolling interests $ 8,907 $ 5,563 Years Ended December 31, (in thousands) 2016 2015 2014 Gross profit $ 92,305 $ 108,416 $ 89,098 Operating, selling, general and administrative expenses 23,662 23,405 21,501 Income from operations 68,643 85,011 67,597 Other expenses (8,775 ) (2,203 ) (1,830 ) Class B preferred return (3,901 ) (6,157 ) (8,707 ) Loss attributable to noncontrolling interest 27,234 10,675 11,023 Net income available to Class A members $ 83,201 $ 87,326 $ 68,083 ADES equity earnings from Tinuum Group $ 41,650 $ 8,651 $ 43,584 As shown above, the Company reported earnings from its equity investment in Tinuum Group of $41.7 million , $8.7 million and $43.6 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. The difference between the Company's proportionate share of Tinuum Group's net income (at its equity interest of 42.5% ) as presented in the table below, and the Company's earnings from its Tinuum Group equity method investment as reported on the Consolidated Statements of Operations relates to the Company receiving distributions in excess of the carrying value of the equity investment, and therefore recognizing such excess distributions as equity method earnings in the period the distributions occur, as discussed below. As shown in the table below, the Company’s carrying value in Tinuum Group was reduced to zero for all years presented, as cumulative cash distributions received from Tinuum Group exceeded the Company's pro-rata share of cumulative earnings in Tinuum Group. The carrying value of the Company's investment in Tinuum Group shall remain zero as long as the cumulative amount of distributions received from Tinuum Group continues to exceed the Company's cumulative pro-rata share of Tinuum Group's net income. For periods during which the ending balance of the Company's investment in Tinuum Group is zero, the Company only recognizes equity earnings from Tinuum Group to the extent that cash distributions are received from Tinuum Group during the period. For periods during which the ending balance of the Company's investment is greater than zero (e.g., when the cumulative earnings in Tinuum Group exceeds cumulative cash distributions received), the Company recognizes its pro-rata share of Tinuum Group's earnings for the period, less any amount necessary to recover the cumulative earnings short-fall balance as of the end of the immediately preceding period. As of December 31, 2016 , the Company's carrying value in Tinuum Group has been reduced to zero, as cumulative cash distributions received from Tinuum Group have exceeded the Company's pro-rata share of cumulative earnings in Tinuum Group. If Tinuum Group subsequently reports net income, the Company will not record its pro-rata share of such net income until the cumulative share of pro-rata income equals or exceeds the amount of its cumulative income recognized due to the receipt of cash distributions. Until such time, the Company will only report income from Tinuum Group to the extent of cash distributions received during the period. Thus, the amount of equity income or loss reported on the Consolidated Statement of Operations may differ from a mathematical calculation of net income or loss attributable to the equity interest based upon the factor of the equity interest and the net income or loss attributable to equity owners as shown on Tinuum Group’s statement of operations. Additionally, for periods during which the carrying value of the Company's investment in Tinuum Group is greater than zero, distributions from Tinuum Group are reported on the Consolidated Statements of Cash Flows as "Distributions from equity method investees, return on investment" within Operating cash flows. For periods during which the carrying value of the Company's investment in Tinuum Group is zero, such cash distributions are reported on the Consolidated Statements of Cash Flows as "Distributions from equity method investees in excess of investment basis" within Investing cash flows. The following table presents the Company's investment balance, equity earnings and cash distributions in excess of the investment balance for the years ended December 31, 2014 through December 31, 2016 ( in thousands ): Description Date(s) Investment balance ADES equity earnings (loss) Cash distributions Memorandum Account: Cash distributions and equity loss in (excess) of investment balance Beginning balance 12/31/2013 $ — $ — $ — $ (12,906 ) ADES proportionate share of net income from Tinuum Group (1) 2014 activity 26,613 26,613 — — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2014 activity (12,906 ) (12,906 ) — 12,906 Cash distributions from Tinuum Group 2014 activity (43,584 ) — 43,584 — Adjustment for current year cash distributions in excess of investment balance 2014 activity 29,877 29,877 — (29,877 ) Total investment balance, equity earnings (loss) and cash distributions 12/31/2014 $ — $ 43,584 $ 43,584 $ (29,877 ) ADES proportionate share of net income from Tinuum Group (1) 2015 activity $ 35,265 $ 35,265 $ — $ — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2015 activity (29,877 ) (29,877 ) — 29,877 Cash distributions from Tinuum Group 2015 activity (8,651 ) — 8,651 — Adjustment for current year cash distributions in excess of investment balance 2015 activity 3,263 3,263 — (3,263 ) Total investment balance, equity earnings (loss) and cash distributions 12/31/2015 $ — $ 8,651 $ 8,651 $ (3,263 ) ADES proportionate share of net income from Tinuum Group (1) 2016 activity $ 35,019 $ 35,019 $ — $ — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2016 activity (3,263 ) (3,263 ) — 3,263 Cash distributions from Tinuum Group 2016 activity (41,650 ) — 41,650 — Adjustment for current year cash distributions in excess of investment balance 2016 activity 9,894 9,894 — (9,894 ) Total investment balance, equity earnings and cash distributions 12/31/2016 $ — $ 41,650 $ 41,650 $ (9,894 ) (1) The amounts of the Company's 42.5% proportionate share of net income as shown in the table above differ from mathematical calculations of the Company’s 42.5% equity interest in Tinuum Group multiplied by the amounts of Net Income available to Class A members as shown in the table above of Tinuum Group's results of operations due to adjustments related to the Class B preferred return and the elimination of Tinuum Group's earnings attributable to RCM6, of which the Company owned 24.95% during the years ended December 31, 2015 and 2014 and for the period from January 1 through March 3, 2016. As noted below, the Company sold its interest in RCM6 on March 3, 2016. As of December 31, 2016 , the Company's future proportionate share of Tinuum Group's net income must exceed approximately $9.9 million before the Company can recognize any earnings from Tinuum Group, unless future, non-refundable cash distributions occur, in which event such distributions would be recognized as earnings from Tinuum Group in the Consolidated Statement of Operations. Additional information related to Tinuum Group pursuant to Regulation S-X Rule 3-09 ("Rule 3-09") of the Securities and Exchange Act of 1934 (the "Exchange Act") is included within Item 15 Exhibits and Financial Statement Schedules ("Item 15") of this Form 10-K. Tinuum Services, LLC In 2010, the Company, together with NexGen, formed Tinuum Services for the purpose of operating and maintaining all of the RC facilities, including those RC facilities leased or sold to third parties. The Company has determined that Tinuum Services is not a VIE and has evaluated the consolidation analysis under the Voting Interest Model. The Company has a 50% voting and economic interest in Tinuum Services, which is equivalent to the voting and economic interest of NexGen. Therefore, as the Company does not hold greater than 50% of the outstanding voting interests, either directly or indirectly, it has accounted for the investment under the equity method of accounting. As of December 31, 2016 and 2015 , the Company’s 50% investment in Tinuum Services was $4.0 million and $4.0 million , respectively. The following tables summarize the assets, liabilities and results of operations of Tinuum Services: As of December 31, (in thousands) 2016 2015 Current assets $ 278,001 $ 186,959 Non-current assets $ 3,426 $ 3,704 Current liabilities $ 97,093 $ 92,675 Non-current liabilities $ 1,488 $ 1,366 Equity $ 7,918 $ 7,935 Noncontrolling interests $ 174,928 $ 88,687 Years Ended December 31, (in thousands) 2016 2015 2014 Gross loss $ (54,644 ) $ (42,496 ) $ (22,168 ) Operating, selling, general and administrative expenses 134,782 161,456 102,757 Loss from operations (189,426 ) (203,952 ) (124,925 ) Other expenses (56 ) (118 ) (62 ) Loss attributable to noncontrolling interest 198,464 213,746 132,237 Net income $ 8,982 $ 9,676 $ 7,250 ADES equity earnings from Tinuum Services $ 4,491 $ 4,838 $ 3,625 Included within the Consolidated Statement of Operations of Tinuum Services during the years ended December 31, 2016 , 2015 and 2014 were losses related to VIE entities that are consolidated within Tinuum Services of $198.5 million , $213.7 million and $132.2 million , respectively. These losses do not impact the Company's equity earnings from Tinuum Services as 100% of those losses are attributable to a noncontrolling interest and eliminated in the calculations of Tinuum Services' net income attributable to the Company's interest. For the years ended December 31, 2016 and 2015 , Tinuum Services did not meet the significant subsidiary test provided in Regulation S-X Rule 1-02(w) ("Rule 1-02(w)") and pursuant to Regulation S-X Rule 3-09 ("Rule 3-09"). RCM6, LLC On February 10, 2014, the Company purchased a 24.95% membership interest in RCM6, which owned a single RC facility that produced and sold RC that qualified for Section 45 tax credits, from Tinuum Group through a combination of an up-front payment and note payable to Tinuum Group. Due to the payment terms of the note purchase agreement, the note payable was periodically negatively amortizing. The balance of the note payable balance as of December 31, 2015 was $14.2 million . In addition to the upfront and note payments, the Company was also subject to quarterly capital calls and variable payments based upon differences in originally forecasted RC production as of the purchase date and actual quarterly production. During the years ended December 31, 2016 , 2015 and 2014 , the Company paid aggregate capital calls and variable payments totaling $0.2 million , $2.4 million and $4.2 million , respectively. RCM6 was determined to be a VIE; however, the Company did not have the power to direct the activities that most significantly impact its economic performance and therefore accounted for RCM6 under the equity method of accounting. As of December 31, 2015 and 2014 , the Company’s ownership in RCM6 was 24.95% . The Company’s investment in RCM6 as of December 31, 2015 was $13.3 million . On March 3, 2016, the Company sold its 24.95% membership interest in RCM6 for a cash payment of $1.8 million and the assumption, by the buyer, of the outstanding note payable made by the Company in connection with its purchase of RCM6 membership interests from Tinuum Group in February 2014. In doing so, the Company recognized a gain on the sale of $2.1 million for the year ended December 31, 2016 , which is included within the Other line item in the Consolidated Statements of Operations . As a result of the sale of its ownership interest, the Company ceased to be a member of RCM6 and, as such, is no longer subject to any quarterly capital calls and variable payments to RCM6. In addition, the Company has no future obligations related to the previously recorded note payable. However, the Company will still receive its pro-rata share of income and cash distributions through its ownership in Tinuum Group based on the RCM6 RC facility lease payments made to Tinuum Group. The following tables summarize the assets and liabilities and results of operations of RCM6 for balance sheet dates and periods ended in which the Company owned a 24.95% membership interest: As of December 31, (in thousands) 2016 2015 Current assets $ — $ 12,240 Non-current assets $ — $ 2,472 Current liabilities $ — $ 1,489 Non-current liabilities $ — $ 7,649 Equity $ — $ 5,574 January 1 - March 3, Year ended December 31, (in thousands) 2016 2015 2014 Gross loss $ (555 ) $ (7,877 ) $ (8,257 ) Operating, selling, general and administrative expenses 360 2,178 2,123 Loss from operations (915 ) (10,055 ) (10,380 ) Other expenses (52 ) (641 ) (666 ) Net loss $ (967 ) $ (10,696 ) $ (11,046 ) ADES equity loss from RCM6 $ (557 ) $ (4,568 ) $ (4,497 ) The purchase of RCM6 resulted in the Company recording a basis difference related to property, plant and equipment and identifiable intangible assets. The amount by which the total of the Company's investment in RCM6 exceeded its proportionate share of the investee's net assets, recorded within the Equity method investments line item in the Consolidated Balance Sheets as of December 31, 2015 was $11.9 million . The difference between the Company's proportionate share of RCM6's net loss and the Company's equity losses noted above related to this depreciation and amortization. For the period from January 1 through March 3, 2016 and the years ended December 31, 2015 and 2014 , the Company decreased its equity method earnings in RCM6 by $0.3 million , $1.9 million and $1.7 million , respectively, due to the basis difference. The following table details the carrying value of the Company's respective equity method investments included within the Equity method investments line item on the Consolidated Balance Sheets and indicates the Company's maximum exposure to loss: As of December 31, (in thousands) 2016 2015 Equity method investment in Tinuum Group $ — $ — Equity method investment in Tinuum Services 3,959 3,968 Equity method investment in RCM6 — 13,264 Total equity method investments $ 3,959 $ 17,232 The Company evaluates the investments for impairment whenever events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable. No impairments were recorded during the years ended December 31, 2016 , 2015 and 2014 . The following table details the components of the Company's respective earnings or loss from equity method investments included within the Earnings from equity method investments line item on the Consolidated Statements of Operations : Year ended December 31, (in thousands) 2016 2015 2014 Earnings from Tinuum Group $ 41,650 $ 8,651 $ 43,584 Earnings from Tinuum Services 4,491 4,838 3,625 Loss from RCM6 (557 ) (4,568 ) (4,497 ) Earnings from equity method investments $ 45,584 $ 8,921 $ 42,712 The following table details the components of additional cash investments related to the Company's respective equity method investments included within the Consolidated Statements of Cash Flows : Year ended December 31, (in thousands) 2016 2015 2014 Purchase of RCM6 interest from Tinuum Group $ — $ — $ 3,153 Contributions to RCM6 223 2,398 3,478 Purchase of and contributions to equity method investments $ 223 $ 2,398 $ 6,631 The following table details the components of the cash distributions from the Company's respective equity method investments included within the Consolidated Statements of Cash Flows . Distributions from equity method investees are reported on the Consolidated Statements of Cash Flows as “return on investment” within Operating cash flows until such time as the carrying value in an equity method investee company is reduced to zero; thereafter, such distributions are reported as “distributions in excess of cumulative earnings” within Investing cash flows. Year ended December 31, (in thousands) 2016 2015 2014 Distributions from equity method investees, return on investment Tinuum Group (1) $ 3,400 $ — $ — Tinuum Services $ 4,500 $ 5,019 $ 2,509 Included in Operating Cash Flows $ 7,900 $ 5,019 $ 2,509 Distributions from equity method investees in excess of cumulative earnings Tinuum Group $ 38,250 $ 8,651 $ 43,584 Included in Investing Cash Flows $ 38,250 $ 8,651 $ 43,584 (1) During the three months ended March 31, 2016, the Company's cumulative share of pro-rata Tinuum Group income exceeded the amount of its cumulative income recognized due to cash being distributed. As such, the Company recognized $3.4 million as "return on investment".

Acquisition

Acquisition	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Acquisition	Acquisition 2015 Acquisition In November 2014 , the Company entered into an agreement with InSyst Ltd. and ClearView Monitoring Solutions Ltd. (collectively "ClearView"), both Israel-based companies specializing in data analytics, to allow the Company the exclusive option to purchase certain assets of ClearView. The Company paid $0.2 million related to this option, which would be applied to the future purchase price if applicable. In January 2015 , the Company notified ClearView that it had elected to exercise its exclusive option to purchase certain assets of ClearView. In March 2015 , the Company acquired the certain assets of InSyst Ltd. and ClearView Monitoring Solutions Ltd., to be operated under the Company's wholly-owned subsidiary, ADA Analytics, for total cash payments of $2.4 million , which was inclusive of value-add tax of $0.4 million . The acquisition was accounted for under the acquisition method of accounting, which requires the total purchase consideration to be allocated to the assets acquired and liabilities assumed based on estimates of fair value. Operating results related to the acquired assets were consolidated into the Company’s results of operations beginning March 6, 2015 . A summary of the purchase consideration and allocation of the purchase consideration is as follows: (in thousands) Purchase consideration: Cash paid $ 2,360 Fair value of liabilities assumed: Accrued liabilities 10 Contingent consideration 451 Total fair value of liabilities assumed 461 Total purchase consideration $ 2,821 Allocation of purchase consideration Receivables $ 360 Property and equipment and other 82 Intangibles - in process research and development 2,379 Total $ 2,821 The transaction called for a series of contingent payments based upon the achievement of certain predetermined sales targets and the completion of certain sales transactions. These contingent payments were classified as contingent consideration. As part of the purchase price, the Company recorded a $0.5 million liability for the contingent consideration based upon the net present value of the Company's estimate of the future payments. During August 2015, as part of a broader strategic restructuring of the Company's business to simplify its operating structure in a manner that creates increased customer focus, better supports sales and product delivery and also aligns the Company’s cost structure as the emissions control market shifts towards compliance solutions for the Federal Mercury and Air Toxics Standards ("MATS"), the Company’s management approved an action to wind down operations of ADA Analytics. As a result of these actions, the Company fully impaired the carrying value of the assets and reversed the liability for the contingent consideration, thereby recognizing net impairment expense in the amount of $1.9 million during 2015. As disclosed in Note 6 , the impairment expense was included as a component of research and development expense for the year ended December 31, 2015 .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Accounts Receivables The following table shows the Company's receivable balance associated with related parties as of December 31, 2016 and 2015 , respectively: As of December 31, (in thousands) 2016 2015 Receivable from related party - Tinuum Group $ 1,934 $ 1,918 Accounts Payable and Advanced Deposits The following table shows the Company's payable balance associated with related parties, exclusive of amounts owed to employees and directors in the normal course of business, as of December 31, 2016 and 2015 , respectively: As of December 31, (in thousands) 2016 2015 Payable to related party - RCM6 $ — $ 270 Prior to 2014, the Company received advanced payments totaling $10.0 million for M-45 TM technology royalties from Tinuum Group. As of December 31, 2016 and 2015 , the Company's remaining advanced deposit balance was zero and $3.0 million , respectively. Revenues The following table shows the revenues recognized with related parties during the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, (in thousands) 2016 2015 2014 Revenues from related party - Tinuum Group $ — $ 55 $ 665 The Tinuum Group revenues in the table above are included within the Chemicals line in the Consolidated Statements of Operations . Other Income The following table shows the other income recognized with related parties during the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, (in thousands) 2016 2015 2014 Royalties, related party - Tinuum Group $ 6,125 $ 10,642 $ 6,410 The above Tinuum Group royalties are included within the Royalties, related party line in the Consolidated Statements of Operations . Notes Payable The following table summarizes the Company's notes payable (net of debt discount and issuance costs) classified according to payment terms, all of which are with related parties: As of December 31, (in thousands) Related Party 2016 2015 Short-term note payable Credit Agreement, net of discount Franklin Mutual $ — $ 12,676 Total Short-term borrowings — 12,676 Current portion of long-term borrowings RCM6 note payable, net of discount Tinuum Group — 1,207 DSI Business Owner note payable DSI Business Owner — 630 Total Current portion of long-term borrowings — 1,837 Total Short-term and current portion of long-term borrowings — 14,513 Long-term borrowings RCM6 note payable, net of discount Tinuum Group — 13,023 DSI Business Owner note payable DSI Business Owner — 489 Total Long-term borrowings — 13,512 Total Borrowings $ — $ 28,025 Credit Agreement On October 22, 2015, the Company entered into a credit agreement for a $15.0 million short-term loan with Franklin Mutual Quest Fund and MFP Investors LLC (the "Lenders"), and Wilmington Trust, National Association, as the administrative agent and collateral agent ("Administrative Agent") (the “Credit Agreement”), which was subsequently amended in 2016 as discussed below. Under the original terms and conditions, the Credit Agreement matured on April 22, 2016 , subject to a three month extension at the Company's option to the extent certain conditions are met. The Credit Agreement bore interest at an annual rate equal to 10.5% and was subject to various prepayment and other premiums if certain events, including a change in control, occur. The Company received net proceeds of $13.5 million and recorded debt discount and debt issuance costs of $1.5 million . The debt discounts and debt issuance costs were amortized to interest expense using the effective interest method over the life of the Credit Agreement. The net proceeds were being used to fund working capital needs and for general operating purposes of the Company and its subsidiaries. All obligations of the Company under the Credit Agreement were unconditionally guaranteed by each of the Company’s wholly-owned domestic subsidiaries (other than ADA Analytics, LLC) and were secured by perfected security interests in substantially all of the assets of the Company and the guarantors, subject to certain agreed upon exceptions. The Lenders were beneficial owners of Common Stock in the Company. The Credit Agreement was approved by the Board and the Audit Committee as a related party transaction. In connection with the Credit Agreement, and the Company's pledge and assignment to the Collateral Agent for all of ADA's equity interests in Tinuum Services, the Lenders required that NexGen consent to a pledge. The Company entered into an Indemnity Agreement with NexGen whereby ADES and ADA agreed to indemnify NexGen from and against any and all losses, claims, damages, liabilities, costs, fees or expenses, which may arise in connection with the Company pledging its Tinuum Services equity interests. The Indemnity Agreement was approved by the Board and the Audit Committee as a related party transaction. On February 8, 2016, the Company entered into the first amendment to the Credit Agreement ("First Amendment") that extended the SEC filings date to March 30, 2016. On March 30, 2016, the Company entered into the second amendment to the Credit Agreement ("Second Amendment"). The Second Amendment extended the maturity date to July 8, 2016, extended the Company's filing date deadline related to its 2015 SEC filings to April 20, 2016, increased the stated interest rate from 10.5% to 15.0% and increased the minimum cash balance requirement from $3.0 million to $3.5 million . The Company incurred approximately $0.6 million in fees related to the Second Amendment. On June 30, 2016, the Company, the required Lenders under the Credit Agreement and the Administrative Agent agreed to terminate the Credit Agreement (the "Payoff Letter") prior to the maturity date of July 8, 2016, effective upon the Company’s $9.9 million prepayment, which amount included the total unpaid principal balance of the loans and advances made to or for the benefit of the Company, together with all accrued but unpaid interest, and the total amount of all fees, costs, expenses and other amounts owed by the Company thereunder, including a prepayment premium. The $9.9 million prepayment amount was paid on June 30, 2016 (the "Payoff Date"). The Payoff Letter included a waiver by the Lenders for a portion of the 4% prepayment premium required by the terms of the Credit Agreement. Tinuum Group - RCM6 Note Payable The Company acquired membership interests in RCM6 from Tinuum Group in February 2014 through an up-front payment and a note payable (the "RCM6 Note Payable"). Due to the payment terms of the note purchase agreement, the RCM6 Note Payable periodically added interest to the outstanding principal balance. The stated rate associated with the note was 1.65% and the effective rate of the note at inception was 20% . Due to the difference between the stated rate and the effective rate, the note payable was carried at a discount of $7.6 million as of December 31, 2015. As described in Note 7 , on March 3, 2016, the Company sold its 24.95% membership interest in RCM6 and, as a result, the Company had no future obligations related to the previously recorded RCM6 Note Payable. DSI Business Owner As of December 31, 2014, the Company terminated the consulting portion of the agreements with the DSI Business Owner. However, according to the terms of the remaining agreements, the Company was required to make all remaining payments structured as a note payable through the third quarter of 2017. In February 2016, the Company entered into an agreement with the DSI Business Owner and settled the remaining amounts owed as of the date of the agreement of approximately $1.1 million for $0.3 million , which was paid during the first quarter of 2016. The difference between the remaining amounts owed and the settlement amount has been included within the Gain on settlement of note payable and licensed technology line item in the Consolidated Statements of Operations for the year ended December 31, 2016 . Highview Long-term License Agreement During 2014, the Company entered into an exclusive, ten -year agreement ("License Agreement") with Highview to utilize certain licensed technology. Pursuant to the License Agreement, the Company recorded a long-term licensed technology asset and related obligation. As of December 31, 2015 , the Company's obligation under the long-term licensing agreement was approximately $1.6 million . On June 15, 2016, the Company entered into an agreement with Highview to terminate the License Agreement in exchange for a one-time payment by the Company of £0.2 million (approximately $0.2 million ). Per the agreement, payment of the termination fee, if any, will only be settled by relinquishing shares of Highview currently owned by the Company equal to £0.2 million . As a result of terminating the License Agreement, the Company wrote off the licensed technology asset, reduced the corresponding long-term liability to the amount of the one-time payment, and recognized a gain of approximately $0.2 million . The gain on the settlement of the Highview license technology obligation is included in the Other income line on the Company's Consolidated Statement of Operations for the year ended December 31, 2016 . Clearview As discussed in Note 8 , on November 20, 2014 , the Company entered into an agreement with InSyst Ltd. and ClearView Monitoring Solutions Ltd., both Israel-based companies specializing in data analytics, to allow the Company the exclusive option to purchase certain assets of ClearView. The Company paid $0.2 million related to this option. Additionally, from November 20, 2014 through the date of the acquisition, the Company paid certain operating costs of Clearview. During the year ended December 31, 2014, the Company recorded expenses of $0.2 million related to these payments within the General and administrative line in the Consolidated Statements of Operations . During 2015, prior to the acquisition, the Company recorded expenses of $0.2 million related to these payments within the General and administrative line in the Consolidated Statements of Operations . Arch Coal License In June 2010, the Company entered into a Development and License Agreement and executed a Securities Subscription and Investment Agreement with Arch Coal, Inc. ("Arch"), a related party as discussed below, pursuant to which the Company licensed, on an exclusive, non-transferable basis, the use of certain of its technology to enhance coal by a proprietary treatment process. The Company received a non-refundable license fee payment from Arch in the amount of $2.0 million and incurred non-reimbursable costs associated with this agreement in the amount of $0.3 million . However, as the agreement does not specify an end date related to the completion of the agreement, the Company has recorded the non-reimbursable costs in the Deposits line item within Other Long-term assets and the non-refundable license fee payment in the Deferred revenue line item in Other long-term liabilities, as shown in Note 11 . Board of Director Matters An Arch designee holds one seat on the Board. The appointment of one designee to the Board was made pursuant to a 2003 Subscription and Investment Agreement, as amended to reflect the effect of the Company's two-for-one stock split in March 2014, whereby the Company’s management agreed to make available one seat on the Board for an Arch designee and to vote all shares and proxies they are entitled to vote in favor of such designee for so long as Arch continues to hold at least 200,000 shares of our common stock. From May 2014 through September 2014, a member of the Board entered into a consulting agreement with the Company to assist in the Restatement process and received compensation of $0.1 million during this period related to the services provided. In addition, as required by the Company's related-party transaction policy, the above noted agreement was approved by the Company’s Audit Committee before being recommended to the Board for approval and was then approved by the disinterested members of the Board. In addition, this individual subsequently served as the Company's Chief Financial Officer from June 2015 through June 2016. Refer to Note 7 for a discussion of transactions entered into with the Company's equity investees.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair Value of Financial Instruments The carrying amounts of financial instruments, including cash and cash equivalents, accounts receivable, accounts payable, deposits and accrued expenses, approximate fair value due to the short maturity of these instruments. Accordingly, these instruments are not presented in the table below. The following table provides the estimated fair values of the remaining financial instruments: As of December 31, 2016 As of December 31, 2015 (in thousands) Carrying Value Fair Value Carrying Value Fair Value Financial Instruments: Investment securities: Investment securities, restricted, long-term $ — $ — $ 336 $ 336 Cost method investment $ 1,016 $ 1,016 $ 2,776 $ 2,776 Borrowings and Notes Payable Short-term borrowings, net of discount and deferred loan costs, related party $ — $ — $ 12,676 $ 12,676 Current portion of notes payable, related parties (1) $ — $ — $ 1,837 $ 1,457 Long-term portion of notes payable, related parties $ — $ — $ 13,512 $ 13,273 Highview technology license payable $ 207 $ 207 $ 519 $ 519 Highview technology license payable, long-term $ — $ — $ 1,038 $ 1,038 Stock appreciation rights, liability-classified equity award $ — $ — $ 742 $ 742 (1) The fair value related to the DSI business owner note payable amounts as of December 31, 2015 was determined using the settlement agreement amount of $0.3 million , as described in Note 9 . Concentration of credit risk The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents and restricted cash. The Company holds such financial instruments at two financial institutions as of December 31, 2016. If those institutions were to be unable to perform their obligations, the Company would be at risk regarding the amount of investment in excess of the federal deposit insurance corporation limits ( $250 thousand ) that would be returned to the Company. Assets and Liabilities Measured at Fair Value on a Recurring Basis The estimated fair values of investment securities are described below. Refer to Note 4 for additional information regarding the Company’s investment securities. Fair value is defined as the price that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. The Company uses the hierarchy prescribed in the accounting guidance for fair value measurements, based upon the available inputs to the valuation and the degree to which they are observable or not observable in the market. The three levels in the hierarchy are as follows: • Level 1 Inputs - Quoted prices (unadjusted) for identical assets or liabilities in active markets that are accessible as of the measurement date. • Level 2 Inputs - Inputs other than quoted prices within Level 1 that are observable either directly or indirectly, including but not limited to, quoted prices in markets that are not active, quoted prices in active markets for similar assets or liabilities and observable inputs other than quoted prices such as interest rates or yield curves. • Level 3 Inputs - Unobservable inputs reflecting the Company’s own assumptions about the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk. Financial instruments carried and measured at fair value on a recurring basis are presented in the table below according to the fair value hierarchy described above. There were no financial instruments carried and measured at fair value on a recurring basis as of December 31, 2016. As of December 31, 2015 Fair Value Measurement Using (in thousands) Level 1 Level 2 Level 3 Fair Value Assets: Investment securities, restricted, long-term $ — $ 336 $ — $ 336 Total assets at fair value $ — $ 336 $ — $ 336 Liabilities: Stock appreciation rights, liability-classified equity award $ — $ 742 $ — $ 742 Total liabilities at fair value $ — $ 742 $ — $ 742 The estimated fair value of certificates of deposit investments securities were estimated to be equal to the deposit value of the investment due to the market interest rates and relative short term nature of the instrument. The Company's experience with these types of investments and the expectations of the current investments held is that they will be satisfied at the current carrying amount. These securities were classified as Level 2. Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis During December 2014 and March 2015, the Company loaned a total of $1.0 million to an independent technology development company exploring energy storage to provide financing to pursue emissions technology projects, bearing annual interest of 8% . Interest and principal were payable at maturity in March 2018. Subsequent to the second loan disbursement, the Company became aware that the independent technology development company exploring energy storage was not awarded contracts that would have utilized their emissions technology. The Company also became aware that without these contracts, the ability of the independent third party to repay these loans was doubtful. As a result, the Company has recorded an allowance against the entire principal balance of the notes receivable, reversed accrued interest and put the note on non-accrual status. During the fourth quarter of 2015, the Company recorded impairments totaling approximately $0.3 million to reduce the carrying value of certain property and equipment that the Company intended to sell at its estimated sales value, less estimated costs to sell. The property and equipment was subsequently sold at auction. Proceeds from the sale of the impaired assets totaled approximately $0.6 million . No gain or loss was recognized on the sale of the property and equipment. Also during the fourth quarter of 2015, the Company sold certain property and equipment having a net book value of approximately $0.1 million . Proceeds from the sale totaled approximately $0.3 million , which resulted in the recognition of a gain on the sale of approximately $0.2 million . During the year ended December 31, 2016 , the Company recorded impairments totaling approximately $0.5 million to reduce the carrying value of certain property and equipment that the Company intended to sell at its estimated sales value, less estimated costs to sell. The property and equipment was subsequently sold at auction. No gain or loss was recognized on the sale of the property and equipment. Additionally, the Company recorded an impairment of approximately $0.8 million included within Equipment sales cost of revenue for the year ended December 31, 2016. As discussed in Note 4 , during the fourth quarter of 2016, the Company recorded an impairment charge of approximately $1.8 million to reduce the carrying value of its cost method investment to its estimated fair value. The fair value measurements represent Level 3 measurements as they are based on significant inputs not observable in the market.

Supplemental Financial Informat

Supplemental Financial Information	12 Months Ended
	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Supplemental Financial Information	Supplemental Financial Information Supplemental Balance Sheet Information The following table summarizes the components of Prepaid expenses and other assets and Other assets as presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Other current assets: Prepaid expenses $ 1,169 $ 2,117 Inventory 16 189 Other 172 — $ 1,357 $ 2,306 Other long-term assets: Deposits $ 263 $ 414 Intangibles 696 1,941 Other long-term assets 323 341 $ 1,282 $ 2,696 The following table details the components of Other current liabilities and Other long-term liabilities as presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Other current liabilities: Accrued consultant incentives $ — $ 369 Accrued interest 618 1,042 Accrued losses on equipment contracts 183 759 Taxes payable 244 521 Deferred revenue 76 682 Warranty liabilities 287 1,197 Deferred rent 369 — Asset retirement obligation 1,312 1,248 Other 928 1,577 $ 4,017 $ 7,395 Other long-term liabilities: Deferred rent $ 38 $ 767 Advance deposit, related party — 2,981 Deferred revenue, related party 2,000 2,000 Other long-term liabilities — 2,604 $ 2,038 $ 8,352 The tables below detail components of Other current liabilities as presented above: The changes in the carrying amount of the Company’s warranty obligations, which do not include amounts for DSI systems, as revenues are deferred until the end of the warranty period, were as follows: As of December 31, (in thousands) 2016 2015 Balance, beginning of year $ 1,197 $ 152 Warranties accrued, net 89 1,337 Warranty claims (899 ) (292 ) Change in estimate related to previous warranties accrued (100 ) — Balance, end of year $ 287 $ 1,197 Included within Other current liabilities is the Company's asset retirement obligation. Changes in the Company's asset retirement obligations were as follows: As of December 31, (in thousands) 2016 2015 Asset retirement obligation, beginning of year $ 1,248 $ 1,188 Accretion 64 60 Asset retirement obligations, end of year $ 1,312 $ 1,248 Supplemental Consolidated Statements of Operations Information The following table details the components of Interest expense in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 453A interest $ 2,490 $ 4,639 $ 3,371 Interest on RCM6 note payable, related party 263 2,468 2,245 Credit agreement interest 1,884 1,180 — Other 429 115 109 $ 5,066 $ 8,402 $ 5,725 The following table details the components of Other in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 Gain on sale of equity method investment $ 2,078 $ — $ — Gain on settlement of note payable and licensed technology 1,019 — — Impairment of cost method investment (1,760 ) — — Gain on termination of sales-type lease 891 — — Other 235 494 26 2,463 494 26

Stockholders Equity

Stockholders Equity	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Stockholders Equity	Stockholders Equity The Company has two classes of capital stock authorized, common stock and preferred stock, which are described as follows: Preferred Stock The Board is authorized to provide out of the unissued shares of Preferred Stock and to fix the number of shares constituting a series of Preferred Stock and, with respect to each series, to fix the number of shares and designation of such series, the voting powers, if any, the preferences and relative, participating, option or other special rights, if any, and any qualifications, limitations or restrictions thereof, of the shares of such series. As of December 31, 2016 and 2015 , there were no shares of Preferred Stock outstanding. Common Stock Holders of common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders. Additionally, holders of common stock are entitled to receive dividends when and if declared by the Board, subject to any statutory or contractual restrictions on payment of dividends and to any restrictions on the payment of dividends imposed by the terms of any outstanding shares of preferred stock. Upon dissolution, liquidation or the sale of all or substantially all of the Company's assets, after payment in full of any amounts required to be paid to creditors and to the holders of preferred stock having liquidation preferences, if any, the holders of shares of common stock will be entitled to receive the Company's remaining assets for distribution on a pro rata basis. Dividends The Company is limited in its ability to pay dividends without concurrently increasing its letters of credit related to the Royalty Award, further discussed in Note 14 . Should the Company pay dividends, the payment of such dividends will be dependent upon earnings, financial condition and other factors considered relevant by the Board and will be subject to limitations imposed under Delaware law. Activity On March 14, 2014, the Company completed a two -for-one stock split of the Company’s common stock, which was effected in the form of a common stock dividend. All share amounts have been retroactively adjusted for the split.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Plans The Company currently has several stock and option plans, including the 2005 Directors’ Compensation Plan (the “2005 Plan”), the Amended and Restated 2007 Equity Incentive Plan, as amended (the “2007 Plan”), the Amended and Restated 2010 Non-Management Compensation and Incentive Plan, as amended (the “2010 Plan”) and the Profit Sharing Retirement Plan, which is a plan qualified under Section 401(k) of the Internal Revenue Code (the “401(k) Plan”) as described below. These plans allow the Company to issue stock-based awards, including common stock, restricted stock, stock options and other rights and benefits under the plans to employees, directors and non-employees. The 2005 Plan - During 2005, the Company adopted the 2005 Plan, which authorized the issuance of shares of common stock and the grant of options to purchase shares of common stock to non-management directors. Under the 2005 Plan, the award of stock is limited to not more than 2,000 shares per individual per year, and the grant of options is limited to 10,000 per individual in total. The aggregate number of shares of common stock reserved for issuance under the 2005 Plan totals 180,000 shares ( 100,000 in the form of stock awards and 80,000 in the form of options). These stock options vest in three equal annual installments beginning one year after the grant date. The 2005 Plan terminated during 2015. The 2007 Plan - During 2007, the Company adopted the 2007 Plan, as amended and restated on July 1, 2013 and amended on July 19, 2012 and February 12, 2014, with two additional amendments, approved by the Board on February 13, 2014 and June 5, 2015. The 2007 Plan permits grants to employees, directors and non-employees of shares of common stock, restricted stock, stock options, cash awards and other rights and benefits under the plan. The maximum annual grant limit for a non-management director on an annual basis is 50,000 shares. The maximum awards available to be granted from the 2007 Plan on an annual basis to any other individual is 400,000 shares. The total number of shares authorized for issuance under the 2007 Plan is 3.6 million . The Compensation Committee of the Board has also approved annual long-term incentive awards for executive officers under the 2007 Plan. The awards vest based on the grantee’s continuous service with the Company, performance measures or a combination of both. Each PSU represents a contingent right to receive shares of the Company’s common stock if the Company meets certain performance measures over the requisite period. Vesting of the PSU's, if at all, occurs no later than January 2 after the conclusion of the third year of the performance period, subject to the grantee’s continuous service and the achievement of certain pre-established performance goals. Amounts vested are measured as of December 31st, immediately prior to the end of the service period, unless the PSU's vest sooner at the target amount as a result of certain transactions pursuant to Section 11 of the 2007 Plan. The number of shares of common stock a participant receives will be increased (up to 200 percent of target levels) or reduced (down to zero ) based on the level of achievement of performance goals. The number of PSU's that may be earned by a participant is determined at the end of the performance period based on the relative placement of the Company’s total stockholder return (“TSR”) for that period with approximately 75% of the award based on the relative performance of the Company’s TSR performance compared to the respective TSRs of a specified group of peer companies and the remaining portion of the award based on the Company’s TSR performance compared to the Russell 3000 Index. The 2010 Plan - During 2010, the Company adopted the 2010 Plan which permits grants of awards to employees, which may be shares, rights to purchase restricted stock, bonuses of restricted stock, or other rights or benefits under the plan. The Company reserved 600,000 shares of its common stock for these purposes. The Plan was amended and restated as of July 19, 2012 to make non-material changes to assure Internal Revenue Code Section 409A compliance. The 401(k) Plan - In 2009, the Company revised its 401(k) Plan to allow the issuance of shares of its common stock to employees to satisfy its obligation to match employee contributions under the terms of the plan in lieu of matching contributions in cash. The Company reserved 600,000 shares of its common stock for this purpose. The value of common stock issued as matching contributions under the plan is determined based on the per share market value of the Company’s common stock generally on quarterly authorization dates. Activity related to the 401(k) Plan is included in Note 15 . Collectively, these plans are called the “Stock Plans.” Expense Restricted Stock - Restricted stock is typically granted with vesting terms of three or five years. The fair value of Restricted Stock Awards ("RSA's") is determined based on the closing price of the Company’s common stock on the authorization date of the grant multiplied by the number of shares subject to the stock award. Compensation expense for RSA's is generally recognized over the entire vesting period on a straight-line basis. Stock Options - Stock options generally vest over three years and have a contractual limit of five years from the date of grant to exercise. The fair value of stock options granted is determined on the date of grant using the Black-Scholes option pricing model and the related expense is recognized on a straight-line basis over the entire vesting period. The following table indicates the weighted-average assumptions that were used related to the awards granted for the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, 2016 2015 2014 Stock options granted: Risk-free interest rate 1.3 % 1.8 % 1.6 % Dividend yield — % — % — % Volatility 78.8 % 74.5 % 80.4 % Expected term (in years) 2.6 5.0 5.0 The Company uses historical data to estimate inputs used in the Black-Scholes option pricing model. Risk-free interest rate - The risk-free interest rate for stock options granted during the period was determined by using a zero-coupon U.S. Treasury rate for the periods that coincided with the expected terms listed above. Dividends - As historically no dividends have been paid, no dividend yield was included in the calculations. Expected volatility - To calculate expected volatility, the historical volatility of the Company's common stock was used. Expected term - The Company’s expected term of options was based upon historical exercise behavior and consideration of the options' vesting and contractual terms. Stock Appreciation Rights - Stock Appreciation Rights ("SAR's") generally vest over three years and have a contractual limit of five years from the date of grant to exercise. The fair value of SAR's granted is determined on the date of grant using the Black-Scholes option pricing model and the related expense is recognized on a straight-line basis over the derived service period of the respective awards. During 2015 , the Company granted a SAR award, and as settlement of the award was out of the control of the Company, the awards were classified as liability-based equity awards and were recorded at the estimated fair value at the grant and remeasured as a liability-based award as of each reporting period. This SAR award was converted to a stock option as of June 30, 2016 as discussed below. The following table indicates the weighted-average assumptions that were used related to the awards granted for the year ended December 31, 2015 . No SAR's were granted during the year ended December 31, 2016 . Year ended December 31, 2015 SAR's granted: Risk-free interest rate 1.8 % Dividend yield — % Volatility 74.5 % Expected term (in years) 5.0 The Company uses historical data to estimate inputs used in the Black-Scholes option pricing model. Risk-free interest rate - The risk-free interest rate for SAR's granted during the period was determined by using a zero-coupon U.S. Treasury rate for the periods that coincided with the expected terms listed above. Dividends - As historically no dividends have been paid, no dividend yield was included in the calculations. Expected volatility - To calculate expected volatility, the historical volatility of the Company's common stock was used. Expected term - The Company’s expected term of SAR's was based upon consideration of the contractual term of the Company’s SAR's of 5 years. PSU's - Compensation expense is recognized for PSU awards on a straight-line basis over a 3 -year service period based on the estimated fair value at the date of grant using a Monte Carlo simulation model. The following table indicates the weighted-average assumptions that were used related to the awards granted for the years ended December 31, 2015 and 2014 . No PSU's were granted during the year ended December 31, 2016 . Years Ended December 31, 2015 2014 PSUs granted: Risk-free interest rate 1.0 % 0.8 % Dividend yield — % — % Volatility 64.3 % 74.5 % Performance period (in years) 3.0 3.0 The Company uses historical data to estimate inputs used in the Monte Carlo pricing model. Risk-free interest rate - The risk-free interest rate for PSU's granted during the period was determined by using a zero-coupon U.S. Treasury rate for the periods that coincided with the expected terms listed above. Dividends - As historically no dividends have been paid, no dividend yield was included in the calculations. Expected volatility - To calculate expected volatility, the historical volatility of the Company's common stock was used. Performance period - The Company’s performance period is based upon the vesting term of the Company’s PSU awards. The Company recorded the following compensation expense related to the Stock Plans: Years Ended December 31, (in thousands) 2016 2015 2014 RSA expense $ 2,021 $ 2,909 $ 2,612 Stock option expense 285 658 117 SAR expense 106 742 — PSU expense 456 2,895 1,983 Total stock-based compensation expense (1) 2,868 7,204 4,712 (1) Amounts for the years ended December 31, 2016 , 2015 and 2014 do not reflect an income tax benefit as a result of a valuation allowance on the Company's deferred tax assets. The Company recorded stock-based compensation expense related to awards to Directors in the General and administrative expense line and all other awards within the Payroll and benefit expense line in the Consolidated Statements of Operations. During the years ended December 31, 2016 , 2015 and 2014 the Company modified the terms of awards granted to 27 , 37 , and 17 employees, respectively, in connection with its restructuring plans and termination of the impacted employees discussed in Note 2 . These modifications resulted in the accelerated vesting and incremental expense related to certain performance-based awards and restricted stock awards. As a result, during 2016 , 2015 and 2014 the Company recognized incremental stock-based compensation of $0.4 million , $3.4 million and $1.0 million respectively, which was included in the Payroll and benefits line item in the Consolidated Statements of Operations. The amount of unrecognized compensation cost as of December 31, 2016 , and the expected weighted-average period over which the cost will be recognized is as follows: As of December 31, 2016 (in thousands) Unrecognized Compensation Cost Expected Weighted-Average Period of Recognition (in years) RSA expense $ 1,335 0.98 Stock option expense 732 0.53 PSU expense 137 0.63 Total unrecognized stock-based compensation expense $ 2,204 0.81 Activity Restricted Stock A summary of the status and activity of non-vested RSA's is presented in the following table: For the Years Ended December 31. 2016 2015 2014 (in thousands, except for share and per share amounts) Shares Weighted- Shares Weighted-Average Shares Weighted-Average Non-vested at beginning of year 134,708 $ 8.49 209,921 $ 13.59 263,989 $ 9.05 Granted 363,758 $ 7.46 127,943 $ 14.97 112,643 $ 24.74 Vested (175,956 ) $ 11.96 (165,796 ) $ 17.51 (118,364 ) $ 15.75 Forfeited (1) (25,163 ) $ 15.58 (37,360 ) $ 19.30 (48,347 ) $ 9.49 Non-vested at end of year 297,347 $ 8.03 134,708 $ 8.49 209,921 $ 13.59 (1) Included within the 2015 forfeited / canceled units are RSA's related to a former executive that were clawed back. The Company recognized $0.1 million within Other Income line item on the Consolidated Statement of Operations related to these awards. The weighted-average grant-date fair value of RSA's granted or modified during the years ended December 31, 2016 , 2015 , and 2014 was $2.7 million , $1.9 million , and $2.8 million , respectively. The total fair value of RSA's vested during the years ended December 31, 2016 , 2015 and 2014 was $2.1 million , $2.9 million and $1.9 million , respectively. During the years ended December 31, 2016 , 2015 and 2014 , the Company accelerated the vesting and expense recognition of 42,852 , 95,088 and 55,106 RSA's granted to 27 , 37 and 17 employees, respectively, in accordance with severance agreements. As a result, during 2016 , 2015 and 2014 , the Company recognized incremental stock-based compensation of $0.3 million , $1.2 million and $1.0 million , respectively, which was included in the Payroll and benefits line item in the Consolidated Statements of Operations. Stock Options A summary of option activity under the Plans is presented below: (in thousands, except for share and per share amounts) Number of Weighted- Aggregate Intrinsic Value Weighted- For the year ended December 31, 2014 Options outstanding, January 1, 2014 317,576 $ 5.07 Options granted 30,000 $ 20.67 Options exercised (260,126 ) $ 4.30 Options expired / forfeited (13,250 ) $ 6.90 Options outstanding, December 31, 2014 74,200 $ 13.76 $ 670 3.0 Options vested and exercisable as of December 31, 2014 34,199 $ 8.44 $ 491 1.6 For the year ended December 31, 2015 Options outstanding, January 1, 2015 74,200 $ 13.76 Options granted 56,250 $ 13.87 Options exercised — $ — Options expired / forfeited (24,200 ) $ 7.59 Options outstanding, December 31, 2015 106,250 $ 15.22 $ — 3.8 Options vested and exercisable as of December 31, 2015 82,915 $ 14.04 $ — 3.9 For the year ended December 31, 2016 Options outstanding, January 1, 2016 106,250 $ 15.22 Options granted (1) 546,196 $ 11.10 Options exercised — $ — Options expired / forfeited (20,000 ) $ 16.90 Options outstanding, December 31, 2016 632,446 $ 11.61 $ 183 4.0 Options vested and exercisable as of December 31, 2016 247,780 $ 13.30 $ 69 3.4 (1) Included in options granted are 243,750 awards granted that were initially granted on a contingent basis and became exercisable as a result of the automatic expiration of the same number of Stock Appreciation Rights, as a result of stockholder approval of Amendment No. 4 of the 2007 Plan. See "Stock Appreciation Rights" section below for a discussion of the provisions of the exchange and incremental expense recognized. The weighted-average grant-date fair value of options granted during the years ended December 31, 2016 , 2015 , and 2014 was $0.5 million , $0.8 million , and $0.6 million , respectively. The total intrinsic value of options exercised during the years ended December 31, 2016 , 2015 and 2014 was zero , zero and $4.9 million , respectively. The total fair value of shares issued as a result of options exercised (measured as of the date of exercise) during the years ended December 31, 2016 , 2015 and 2014 was zero , zero and $6.1 million , respectively. Cash flows resulting from excess tax benefits, if any, are classified as part of cash flows from financing activities. Excess tax benefits are realized tax benefits from tax deductions for vested RSA's, settled PSU's and exercised options in excess of the deferred tax asset attributable to stock compensation costs for such equity awards. The Company recorded no excess tax benefits for the years ended December 31, 2016 , 2015 , and 2014 . During 2015, approximately $0.5 million of stock-based compensation expense was recognized as a result of granting an executive officer stock options which were immediately vested, with an exercise price of $13.87 per option. SAR's A summary of SAR activity under the Plans is presented below: (in thousands, except for share and per share amounts) Number of Weighted- Aggregate Intrinsic Value Weighted- For the year ended December 31, 2015 SAR's outstanding as of January 1, 2015 — $ — Granted 243,750 $ 13.87 Exercised — $ — Expired / forfeited — $ — SAR's outstanding as of December 31, 2015 243,750 $ 13.87 $ — 4.5 SAR's vested and exercisable as of December 31, 2015 43,750 $ 13.87 $ — — For the year ended December 31, 2016 SAR's outstanding as of January 1, 2016 243,750 $ 13.87 Granted — $ — Exercised — $ — Expired / forfeited (243,750 ) $ 13.87 SAR's outstanding as of December 31, 2016 — $ — $ — — SAR's vested and exercisable as of December 31, 2016 — $ — $ — — In June 2016, the Company's stockholders approved Amendment No. 4 to the 2007 Plan, which triggered an automatic expiration of the Stock Appreciation Rights and an equal number of stock options being exercisable and no longer granted on a contingent basis. Upon approval, all existing SAR's expired under this provision. The Company recorded incremental expense of $0.1 million to stock-based compensation related to the change in fair value of the SAR's prior to the reclassification date. Upon reclassification, the impact to Additional paid-in capital was a $0.9 million increase. The Company had no SAR's outstanding as of December 31, 2016 . PSU's A summary of the status and activity of non-vested PSU's is presented in the following table: For the Years Ended December 31. 2016 2015 2014 (in thousands, except for share and per share amounts) Units Weighted-Average Units Weighted-Average Units Weighted-Average Non-vested at beginning of year 169,334 $ 26.38 142,357 $ 30.65 89,578 $ 26.04 Granted (1) — $ — 69,218 $ 20.10 57,547 $ 37.45 Vested (1) (119,818 ) $ 26.87 (13,763 ) $ 30.52 — $ — Forfeited / Canceled (1) (2) — $ — (28,478 ) $ 30.44 (4,768 ) $ 26.04 Non-vested at end of year 49,516 $ 25.20 169,334 $ 26.38 142,357 $ 30.65 (1) The number of units shown in the table above are based on target performance. The final number of shares of common stock issued may vary depending on the achievement of market conditions established within the awards, which could result in the actual number of shares issued ranging from zero to a maximum of two times the number of units shown in the above table. (2) Included within the 2015 forfeited / canceled units are PSU's related to a former executive that were clawed back. The Company recognized $0.2 million within Other Income line item on the Consolidated Statement of Operations related to these awards . The weighted-average grant date fair value of PSU's granted during the years ended December 31, 2016 , 2015 , and 2014 was zero , $1.4 million , and $2.2 million , respectively. The PSU's granted will remain unvested until the third anniversary date of their issuance, at which time the actual number of vested shares will be determined based upon the actual price performances of the Company’s common stock relative to a broad stock index and a peer group performance index. During the years ended December 31, 2016 , 2015 , and 2014 , the Company modified and accelerated certain PSU's that were granted to former executive officers in 2013, 2014, and 2015. The Company recorded incremental expense of $0.1 million , $2.1 million , and $0.2 million in the Payroll and benefits line item in the Consolidated Statement of Operations. The following table shows the PSUs that were settled by issuing the Company's common stock relative to a peer group performance index and broad stock index. Year of Grant Net Number of Issued Shares upon Vesting Shares Withheld to Settle Tax Withholding Obligations TSR Multiple Range Russell 3000 Multiple Low High Low High For the year ended December 31, 2016 2013 38,706 1,572 0.63 1.00 — — 2014 11,487 — 0.63 0.63 — — 2015 13,529 — 0.50 0.50 — — For the year ended December 31, 2015 2013 8,768 3,954 1.75 1.75 2.00 2.00 2014 2,506 1,145 0.63 0.75 — 0.75 Other Matters Cash received from the exercise of stock options for the years ended December 31, 2016 , 2015 and 2014 was zero , zero , and $0.2 million , respectively. There were no other cash receipts during these years from the exercise of other share-based compensation arrangements.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings The Company is involved in certain legal actions, described below. The outcomes of these legal actions are not within the Company’s complete control and may not be finalized for prolonged periods of time. In the described actions, the claimants seek monetary damages and other penalties. In accordance with U.S. GAAP, the Company records a liability in the Consolidated Financial Statements for loss contingencies when a loss is known or considered probable and the amount can be reasonably estimated. In the described lawsuits, the Company has entered into settlement agreements, with the claimants setting forth the specific or maximum amount of monetary damages required to settle each action. In the described government investigation, the Company has reached agreement in principle with regard to the amount of monetary damages required to settle such action. Therefore, such amounts are probable and reasonably estimable. The Company cannot predict the timing of final resolution or the final outcome of any pending legal proceedings as described in the paragraphs below, nor can it provide any assurance that the ultimate resolution of any such matter will not have a material adverse effect on the Company's consolidated financial position, results of operations or cash flows. Securities class action lawsuit: United Food and Commercial Workers Union v. Advanced Emissions Solutions, Inc. , No. 14-cv-01243-CMA-KMT (U.S. District Court, D. Colo.) A class action lawsuit against ADES and certain of its current and former officers was filed in May 2014 in the federal court in Denver, Colorado alleging that ADES and other defendants misrepresented to the investing public the Company’s financial condition and its financial controls to artificially inflate and maintain the market price of ADES’s common stock. In May 2016, the parties reached an agreement in principle to settle this litigation, and on June 30, 2016, the parties entered into a Stipulation and Agreement of Settlement to resolve the action in its entirety. On February 10, 2017, we received an order and final judgment that the lawsuit was settled, and the entire case has been dismissed with prejudice. The settlement agreement for this case contains no admission of liability, and all of the defendants in this litigation have expressly denied, and continue to deny, all allegations of wrongdoing or improper conduct. The Company’s insurance carriers funded the full settlement in November 2016. However, until an order and final judgment of the lawsuit having been settled was received, the funded settlement did not relieve the Company's recorded liability. As of December 31, 2016, the Company had a recorded liability of $4.0 million in connection with the Denver Settlement as the losses in connection with this matter were probable and reasonably estimable under U.S. GAAP. The liability was originally recorded as of June 30, 2016 in the Legal settlements and accruals line item of the Consolidated Balance Sheet. As of December 31, 2016 , the Company also had a recorded receivable of $4.0 million in connection with the Denver Settlement as the Company's insurance carriers funded the full settlement but final judgment was not receive as December 31, 2016 . Stockholder derivative lawsuits: In Re Advanced Emissions Solutions, Inc. Shareholder Derivative Litigation , No. 2014CV-30709 (District Court, Douglas County, Colorado) (consolidated actions). In June and July 2014, stockholder derivative actions were filed in the Douglas County District Court and in the Colorado District Court for the City and County of Denver against certain of the Company’s current and former officers and directors, along with the Company as a "nominal defendant." In May 2016, the parties reached an agreement in principle to settle this stockholder derivative action, and on September 30, 2016, the parties entered into a Stipulation and Agreement of Settlement to resolve the action in its entirety. The Stockholder Derivative Settlement was approved and the case was closed on January 4, 2017. The settlement agreement for this case contained no admission of liability, and all of the defendants in this stockholder derivative action have expressly denied, and continue to deny, all allegations of wrongdoing or improper conduct. The Company’s insurance carriers funded the full settlement in January 2017. As of December 31, 2016 , the Company had a recorded liability of $0.6 million in connection with the Derivative Settlement as the losses in connection with this matter were probable and reasonably estimable under U.S. GAAP. The liability was originally recorded as of June 30, 2016 in the Legal settlements and accruals line item of the Consolidated Balance Sheet. As of December 31, 2016 , the Company also had a recorded receivable in connection with the Derivative Settlement of $0.6 million , which was originally recorded as of June 30, 2016, as the Company's insurance carriers subsequently funded the fee award in January 2017. SEC Inquiry On April 7, 2014, the SEC Staff informed the Company that it had initiated the SEC Inquiry to determine if violations of the federal securities laws had occurred, and in September 2014 the SEC issued a formal order of investigation. The SEC Inquiry generally pertains to the restatement of the Company’s financial statements and internal controls processes, as described in Note 2 to the Consolidated Financial Statements of the Company included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2014 . The Company cooperated with the SEC by providing information and documents to the SEC on an ongoing basis. In July 2016, the SEC Staff communicated to the Company that it would recommend to the SEC that it authorize a settlement with the Company on terms that include payment of a civil monetary penalty of $0.5 million . This penalty will not be funded by the Company’s insurance carriers. The SEC must approve the SEC Staff recommendation and any final settlement or relief. As a result of the communication from the SEC Staff, the Company recorded a liability as of June 30, 2016 for the payment of monetary penalties in connection with the SEC Inquiry in the amount of $0.5 million as the losses in connection with this matter were both probable and reasonably estimable under U.S. GAAP. The recorded liability was based on an agreement in principle with SEC Staff subject to approval by the SEC. The liability was recorded in the Legal settlements and accruals line item on the Consolidated Balance Sheets . The expense recognized related to this accrual was included in the Other line item in the Consolidated Statements of Operations for the year ended December 31, 2016 . Settlement and Royalty Indemnity In August 2008, Norit International N.V. f/k/a Norit N.V. ("Norit") filed a lawsuit against the Company asserting claims for misappropriation of trade secrets and other claims related to the Company's ADA Carbon Solutions, LLC joint venture ("Carbon Solutions") that built an activated carbon manufacturing plant (the “Red River Plant”). In August 2011 , the Company and Norit entered into a settlement agreement whereby the Company paid amounts related to the non-solicitation breach of contract claim, and ADA was also required to pay additional damages related to certain future revenues generated from the equity method investment through the second quarter of 2018 (the "Royalty Award"). Payments of amounts due under the Royalty Award for each quarter are payable three months after such quarter ends. In October 2011 , an arbitration panel endorsed and confirmed the terms of the settlement agreement. Additionally, during November 2011, the Company entered into an Indemnity Settlement Agreement whereby the Company agreed to settle certain indemnity obligations asserted against the Company related to the Norit litigation and relinquished all of its equity interest in Carbon Solutions and amended the Intellectual Property License Agreement dated October 1, 2008 between the Company and Carbon Solutions. In the event that the Company declares or otherwise issues a dividend to any or all of its stockholders prior to January 1, 2018, other than repurchases of common stock under employee stock plans, the Company must increase its letter of credit amounts as collateral for payments due to Norit, equal to 50% of the aggregate fair market value of such dividends. Additionally, the first time that the Company achieves earnings in excess of $20.0 million for a fiscal year ended prior to January 1, 2018, the Company must also increase its letter of credit amounts as collateral by $5.0 million for payments due to Norit. However, the maximum total letter of credit increase related to the combination of dividends or earnings is $7.5 million . As such, upon the filing of this Report, the Company will increase its letter of credit by $5.0 million . During the fourth quarter of 2016, the Company revised its estimate for future Royalty Award payments based in part on an updated forecast provided to the Company from Carbon Solutions. This forecast included a material reduction in estimated future revenues generated at the Red River Plant. Based primarily on the updated forecast, the Company recorded a $4.0 million reduction to its Royalty Award accrual as of December 31, 2016. The following table summarizes the Company's legal settlements and accruals as described above, which are presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Settlement and Royalty Indemnification $ 5,656 $ 6,502 Legal settlements 5,050 — Legal settlements and accruals, current 10,706 6,502 Settlement and Royalty Indemnification, long-term 5,382 13,797 Total legal settlements and accruals $ 16,088 $ 20,299 Future amounts to be paid related to the Royalty Award may differ from current estimates due to future adjusted sales of activated carbon from the Red River Plant. The receivables related to the Denver Settlement and the Stockholder Derivative Action are shown with the Receivables, net line item in the Consolidated Balance Sheets in the same amounts as the respective liabilities. Other Commitments and Contingencies Tinuum Group The Company also has certain limited obligations contingent upon future events in connection with the activities of Tinuum Group. The Company, NexGen and two entities affiliated with NexGen have provided GSFS with limited guaranties (the “Tinuum Group Party Guaranties”) related to certain losses it may suffer as a result of inaccuracies or breach of representations and covenants. The Company also is a party to a contribution agreement with NexGen under which any party called upon to pay on a Tinuum Group Party Guaranty is entitled to receive contribution from the other party equal to 50% of the amount paid. No liability or expense provision has been recorded by the Company related to this contingent obligation as the Company believes that it is not probable that a loss will occur with respect to Tinuum Group Party Guaranties. Consultant Obligation On January 1, 2012 , the Company entered into a residual payment agreement with a former consultant who was involved in the development and deployment of RC technologies. Pursuant to the agreement, the Company was required to make annual payments based upon Tinuum Group's RC production and sale from January 1, 2012 through June 30, 2015 . These expenses were recorded within the Legal and professional fees line item in the Consolidated Statements of Operations and were recorded as RC production occurred. During the years ended December 31, 2015 and 2014 , the Company recorded expenses under this agreement of $0.3 million and $1.4 million , respectively. In January 2016, the Company made the final payment of approximately $0.3 million related to this obligation. Line of Credit In September 2013, ADA, as borrower, and the Company, as guarantor, entered into the 2013 Loan and Security Agreement with a bank (the "Lender") for an aggregate principal amount of $10 million that was secured by certain amounts due to the Company from certain Tinuum Group RC leases (the "Line of Credit"). The Line of Credit was amended nine times from the period from December 2, 2013 through November 25, 2016, most notably to extend the maturity date with each amendment. In addition, during this period, the Lender also granted 10 waivers related to various transactions and obligations to provide financial information to the Lender. Covenants in the Line of Credit included a borrowing base limitation that was based on a percentage of the net present value of ADA’s portion of payments due to Tinuum Group from the RC leases. The Line of Credit also contained other affirmative and negative covenants and customary indemnification obligations of ADA to the Lender and provided for the issuance of letters of credit provided that the aggregate amount of the letters of credit plus all advances then outstanding did not exceed the calculated borrowing base. The Company guarantees the obligations and agreements of ADA under the Line of Credit. Amounts outstanding under the Line of Credit bear interest payable monthly at a rate per annum equal to the higher of 5% or the “Prime Rate” (as defined in the Line of Credit) plus 1% . As a result of various covenant violations, the Company had no borrowing availability under the Line of Credit from inception through November 29, 2016. On November 30, 2016, ADA, as borrower, the Company, as guarantor, and the Lender entered into the Tenth Amendment of 2013 Loan and Security Agreement (the "Tenth Amendment"). The Tenth Amendment increases the Line of Credit to $15 million from $10 million , extends the maturity date of the Line of Credit to September 30, 2017, permits the Line of Credit to be used as collateral (in place of restricted cash) for letters of credit related to equipment projects, the Royalty Award and certain other agreements, additionally secures the Line of Credit with amounts due to the Company from an additional existing Refined Coal facility lease, which amounts also now factor into the borrowing base limitation, and amends certain financial covenants. Pursuant to the Tenth Amendment, the Company was required to, among other things, pay a new origination fee of $0.1 million and associated legal preparation fees of the Lender, maintain a deposit account with the Lender with a minimum balance of $6.0 million initially and $3.0 million after certain conditions are met, and maintain minimum trailing twelve month EBITDA (earnings before interest, taxes, depreciation and amortization as defined in the Tenth Amendment) of $24.0 million . As of December 31, 2016 , there were no outstanding amounts under the Tenth Amendment, nor were any amounts drawn during 2016. However, due to outstanding letters of credits offsetting the line, the Company's borrowing availability has been reduced to $13.2 million as of December 31, 2016 . Letters of Credit The Company has letters of credit ("LOC") with two financial institutions related to equipment projects, the Royalty Award and certain other agreements. The following tables summarize the LOC outstanding and related collateral reported in the Consolidated Balance Sheets : As of December 31, 2016 (in thousands) LOC Outstanding Utilization of LOC Availability Restricted Cash Restricted cash, long-term Investment securities, restricted, long-term Contract performance - equipment systems $ 1,855 $ 1,776 $ 86 $ — $ — Royalty award 7,150 — 7,150 — — Other 6,500 — 6,500 — — Total LOC outstanding $ 15,505 $ 1,776 $ 13,736 $ — $ — As of December 31, 2015 (in thousands) LOC Outstanding Utilization of LOC Availability Restricted Cash Restricted cash, long-term Investment securities, restricted, long-term Contract performance - equipment systems $ 5,556 — $ 728 $ 4,830 $ — Royalty award 6,150 — — 6,150 — Other 328 — — — 336 Total LOC outstanding $ 12,034 $ — $ 728 $ 10,980 $ 336 Restricted balances may exceed the letters of credit outstanding due to interest income earned on the restricted assets. The following tables summarizes the expiration periods of the letters of credit based on the ultimate maturity date of the letters of credit as of December 31, 2016 : Expiration of Letters of Credit as of December 31, 2016 (in thousands) Less than 1 year 1-3 years 4-5 years After 5 years Letters of credit $ 10,855 $ 4,650 $ — $ — Performance Guarantee on Equipment Systems In the normal course of business related to ACI and DSI systems, the Company may guarantee certain performance thresholds during a discrete performance testing period that do not extend beyond six months from the initial test date, the commencement of which is determined by the customer. Performance thresholds include such matters as the achievement of a certain level of mercury removal and other emissions based upon the injection of a specified quantity of a qualified activated carbon or other chemical at a specified rate given other plant operating conditions, and availability of equipment and electric power usage. In the event the equipment fails to perform as specified during the testing period, the Company may have an obligation to correct or replace the equipment. In the event the level of mercury removal is not achieved, the Company may have a “make right” obligation within the contract limits. During 2015, the Company began working to modify and correct two performance guarantee issues related to EC systems that were installed during 2015. No revenue was recognized on these two contracts until the performance guarantees were resolved and contract obligations were substantially complete. During the third quarter of 2016, the Company passed performance testing on both systems and revenues on both systems were recognized. As a result of the resolution of the performance guarantees, the Company incurred approximately $0.9 million of costs on the ACI systems to pass the performance guarantees. Additional performance guarantee claims, if incurred, would be included within the Equipment sales cost of revenue line of the Consolidated Statements of Operations. Purchase Obligations The Company does not have any future purchase obligations as of December 31, 2016 . DOE Audits Certain of the Company's completed and current contracts awarded by the DOE and related industry participants remain subject to adjustments as a result of future government audits. The Company's historical experience with these audits has not resulted in significant adverse adjustments to amounts previously received; however the audits for the years 2010 and later have not been finalized. Operating Lease Obligations The Company leases office, warehouse and laboratory space in Highlands Ranch, Colorado under operating leases. As of December 31, 2016 , the Company leased approximately 52,869 square feet under approximately 3 leases. Original lease terms ranged from 4 to 7 years. Certain of these leases have options permitting renewals for additional periods. In addition to minimum fixed payments, a number of leases contain annual escalation clauses which are related to increases in the inflation index. In December 2016, the Company entered into a lease termination related to its leased office spaced, in which the Company paid a $0.3 million lease termination fee. The lease termination is effective February 2017. Also in December 2016, the Company entered into a new office lease in Highlands Ranch, Colorado effective February 2017. Annual minimum commitments under the leases as of December 31, 2016 are as follows: Years Ending December 31, Operating Lease Commitments (in thousands) 2017 $ 290 2018 268 2019 174 2020 55 Thereafter — Total $ 787 Rent expense incurred for the years ended are as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Rent expense $ 847 $ 1,838 $ 1,531

Defined Contributions Savings P

Defined Contributions Savings Plan	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Defined Contributions Savings Plan	Defined Contributions Savings Plan The Company has an employee retirement plan (the "401(k) Plan") that provides eligible employees of the Company an opportunity to accumulate retirement funds. The Company makes discretionary matching contributions to the 401(k) Plan in the form of cash or historically in the form of its common stock. The following table presents the amount the Company recognized as expense within the Payroll and benefits line item in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 401(k) employer expense $ 173 $ 439 $ 509 Due to the Restructuring discussed in Note 2 , there was a decrease in employer expense related to the 401(k) Plan for the year ended December 31, 2016 .

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The provision for income taxes consists of the following: Years Ended December 31, (in thousands, except for rate) 2016 2015 2014 Current portion of income tax expense (benefit): Federal $ — $ — $ — State 458 20 296 458 20 296 Deferred portion of income tax (benefit) expense: Federal (61,396 ) — — State — — — (61,396 ) — — Total income tax (benefit) expense $ (60,938 ) $ 20 $ 296 Effective tax rate (166 )% — % 18 % A reconciliation of expected federal income taxes on income from operations at statutory rates with the expense (benefit) for income taxes is as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Federal statutory rate $ 12,859 $ (10,542 ) $ 589 State income taxes, net of federal benefit 987 (781 ) 31 Disallowed compensation — — 721 Permanent differences 84 35 52 Tax credits (2,419 ) (38,998 ) (25,607 ) Valuation allowances (72,359 ) 50,066 23,794 Changes in state effective rates (125 ) (243 ) 716 Stock-based compensation 36 487 — Other (1 ) (4 ) — (Benefit) expense for the provision for income taxes $ (60,938 ) $ 20 $ 296 Deferred income taxes are provided for the effects of temporary differences between the tax basis of an asset or liability and its reported amount in the accompanying Consolidated Balance Sheets. These temporary differences result in taxable or deductible amounts in future years. Details of the Company’s deferred tax assets and liabilities are summarized as follows: As of December 31, (in thousands) 2016 2015 Deferred tax assets Settlement and Royalty Indemnification $ 4,264 $ 7,807 Deferred revenues and loss contract provisions 268 2,899 Employee related liabilities 3,796 4,598 Intangible assets 1,518 1,733 Equity method investments 12,326 7,500 Net operating loss carryforward 13,341 23,193 Tax credits 99,903 97,484 Deposits on contracts — 1,146 Other 2,109 2,118 Total deferred tax assets 137,525 148,478 Less valuation allowance (75,910 ) (148,269 ) Deferred tax assets 61,615 209 Less: Deferred tax liabilities Property and equipment and other (219 ) (209 ) Total deferred tax liabilities (219 ) (209 ) Net deferred tax assets $ 61,396 $ — For 2016 , the Company recorded an income tax benefit of $60.9 million compared to an income tax expense of zero for 2015 . The income tax benefit for 2016 was primarily due to the $61.4 million reversal of the valuation allowance of the Company’s net deferred tax assets. Accounting for income taxes requires that companies assess whether a valuation allowance should be recorded against their deferred tax asset based on an assessment of the amount of the deferred tax asset that is “more likely than not” to be realized. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount that is more likely than not to be realized. The Company assesses the valuation allowance recorded against deferred tax assets at each reporting date. The determination of whether a valuation allowance for deferred tax assets is appropriate requires the evaluation of positive and negative evidence that can be objectively verified. Consideration must be given to all sources of taxable income available to realize the deferred tax asset, including, as applicable, the future reversal of existing temporary differences, future taxable income forecasts exclusive of the reversal of temporary differences and carryforwards, taxable income in carryback years and tax planning strategies. In estimating taxes, the Company assesses the relative merits and risks of the appropriate tax treatment of transactions taking into account statutory, judicial, and regulatory guidance. The Company has historically recorded a valuation allowance for all of its deferred tax assets, primarily due to its historical three-year cumulative loss position. However, the Company concluded that, as of December 31, 2016 , it is more likely than not the Company will generate sufficient taxable income within the applicable NOL and tax credit carry-forward periods to realize $61.4 million of its net deferred tax assets and, therefore, reversed $61.4 million of the valuation allowance after utilizing $11.0 million during the current year. This conclusion was reached after weighing all of the evidence and determining that the positive evidence outweighed the negative evidence. The positive evidence considered by management in arriving at its conclusion to partially reverse the valuation allowance includes factors such as: (1) emergence from the previous three-year cumulative loss position during the fourth quarter of 2016, (2) completion of four consecutive quarters of profitability and (3) forecasts of continued future profitability. These forecasts are based under several potential scenarios materially derived from currently contracted business within the RC segment that support the partial utilization of deferred tax assets attributable to temporary differences that do not expire and federal NOLs and tax credits prior to their expiration between 2031 through 2036. As a result of the partial reversal, the Company’s net deferred tax assets were $61.4 million as of December 31, 2016 , net of a valuation allowance of $75.9 million . As of December 31, 2015 , the Company had recorded a valuation allowance against the net deferred tax assets of $148.3 million to reflect the estimated amount of deferred tax assets that may not be realized. During 2016 , the Company’s valuation allowance decreased by $72.4 million primarily due to the partial release of the previously recorded full valuation allowance. The following table presents the approximate amount of federal and state net operating loss carryforwards and federal tax credit carryforwards available to reduce future taxable income, along with the respective range of years that the net operating loss and tax credit carryforwards would expire if not utilized: As of December 31, (in thousands) 2016 Beginning expiration year Ending expiration year Federal net operating loss carryforwards $ 31,699 2031 2036 State net operating loss carryforwards $ 57,600 2021 2036 Federal tax credit carryforwards $ 99,879 2031 2036 The following table sets forth a reconciliation of the beginning and ending unrecognized tax benefits on a gross basis for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, (in thousands) 2016 2015 2014 Balance as of January 1 $ — $ — $ — Increases for tax positions of current year 54 — — Balance as of December 31 54 — — The Company did not record any adjustments or recognize interest expense for uncertain tax positions for the years ended December 31, 2016 , 2015 and 2014 . Interest and penalties related to uncertain tax positions are accrued and included in the Interest expense line item in the Consolidated Statements of Operations . Additionally, the Company recognizes interest expense related to tax treatment of RC facilities at Tinuum Group in the Interest expense line item in the Consolidated Statements of Operations. Additional information related to these interest amounts is included in Note 11 . The Company files income tax returns in the U.S. and in various states. The Company is no longer subject to U.S. federal examinations by tax authorities for years before 2013 . The Company is generally no longer subject to State and local examinations by tax authorities for years before 2012 .

Business Segment Information

Business Segment Information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Business Segment Information	Business Segment Information Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by a company's chief operating decision maker ("CODM"), or a decision making group, in deciding how to allocate resources and in assessing financial performance. As of December 31, 2016 , the Company's CODM was the Company's CEO. The Company's operating and reportable segments are organized by products and services provided. As of December 31, 2016, the Company has two reportable segments: (1) Refined Coal ("RC"); and (2) Emissions Control ("EC"). The business segment measurements provided to and evaluated by the CODM are computed in accordance with the principles listed below: • The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies except as described below. • Segment revenue includes the Company's equity method earnings and losses from the Company's equity method investments. Segment revenue also includes the Company's royalty earnings from Tinuum Group and income related to sales-type leases. • Segment operating income (loss) includes the Company's equity method earnings and losses from the Company's equity method investments, royalty earnings from Tinuum Group (including depreciation and amortization expense) and gains related to sales of equity method investments. However, segment operating income (loss) excludes Payroll and benefits , Rent and occupancy , Legal and professional fees , and General and administrative ("Corporate general and administrative expenses") unless otherwise specifically included, as the Company does not allocate those amounts between segments. • All items not included in operating income, except as noted below, are excluded from the RC and EC segments. As of December 31, 2016 and December 31, 2015 , substantially all of the Company's material assets are located in the U.S. and all significant customers are either U.S. companies or the U.S. Government. The following table presents the Company's operating segment results for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, (in thousands) 2016 2015 2014 Revenues: Refined Coal: Earnings in equity method investments $ 45,584 $ 8,921 $ 42,712 Consulting services — 55 665 Royalties, related party 6,125 10,642 6,410 51,709 19,618 49,787 Emissions Control: Equipment sales 46,949 60,099 12,044 Chemicals 3,025 888 391 Consulting services 648 1,697 3,823 50,622 62,684 16,258 Total segment reporting revenues $ 102,331 $ 82,302 $ 66,045 Adjustments to reconcile to reported revenues: Refined Coal: Earnings in equity method investments $ (45,584 ) $ (8,921 ) $ (42,712 ) Royalties, related party (6,125 ) (10,642 ) (6,410 ) (51,709 ) (19,563 ) (49,122 ) Total reported revenues $ 50,622 $ 62,739 $ 16,923 Segment reporting operating income (loss) Refined Coal (1) $ 51,264 $ 12,131 $ 42,094 Emissions Control (2) 7,334 (7,583 ) (13,348 ) Total segment operating income $ 58,598 $ 4,548 $ 28,746 (1) Included within the RC segment operating income for the year ended December 31, 2016 is a $2.1 million gain on the sale of RCM6 and for the years ended December 31, 2016 and 2015 , 453A interest expense of $2.5 million and $4.6 million , respectively, and interest expense related to the RCM6 note payable of $0.3 million and $2.5 million , respectively. (2) Included within the EC segment operating income for the year ended December 31, 2016 is a $0.9 million gain related to a termination of a sales-type lease. A reconciliation of reportable segment income to the Company's consolidated net income is as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Segment income Total reported segment operating income $ 58,598 $ 4,548 $ 28,746 Adjustments to reconcile to net income (loss) attributable to the Company Corporate payroll and benefits (9,415 ) (14,842 ) (12,621 ) Corporate rent and occupancy (1,187 ) (707 ) (694 ) Corporate legal and professional fees (8,230 ) (15,199 ) (9,514 ) Corporate general and administrative (3,811 ) (3,640 ) (3,980 ) Corporate depreciation and amortization (608 ) (578 ) (354 ) Corporate interest (expense) income, net (2,334 ) 24 74 Other income (expense), net 3,727 273 26 Income tax benefit (expense) 60,938 (20 ) (296 ) Net income (loss) $ 97,678 $ (30,141 ) $ 1,387 Corporate general and administrative expenses include certain costs that benefit the business as a whole but are not directly related to one of our segments. Such costs include but are not limited to accounting and human resources staff, information systems costs, legal fees, facility costs, audit fees and corporate governance expenses. Segment assets are as follows as of the dates presented: As of December 31, (in thousands) 2016 2015 Assets: Refined Coal $ 6,310 $ 19,507 Emissions Control 24,551 31,467 All Other and Corporate 76,435 9,801 Consolidated $ 107,296 $ 60,775

Major Customers

Major Customers	12 Months Ended
	Dec. 31, 2016
Major Customers Disclosure [Abstract]
Major Customers	Major Customers Revenues from unaffiliated customers who represent 10% or more of the Company’s revenues in any one year were as follows: Years Ended December 31, Customer Revenue Type Segment(s) 2016 2015 2014 A Equipment sales EC 21% 3% —% B Equipment sales, Consulting services EC 14% 16% 37% C Equipment sales, Consulting services, Other EC 1% 2% 24% D Consulting services EC —% 11% 8% E Equipment sales EC —% 15% —%

Quarterly Financial Results (un

Quarterly Financial Results (unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Results (unaudited)	Quarterly Financial Results (unaudited) Summarized quarterly results for the two years ended December 31, 2016 and December 31, 2015 , respectively, are as follows: For the Quarter Ended (in thousands, except per share data) December 31, 2016 September 30, 2016 June 30, 2016 March 31, 2016 Revenues $ 3,604 $ 15,710 $ 8,951 $ 22,357 Cost of revenues, exclusive of operating expenses shown below 3,478 13,259 5,769 17,311 Other operating expenses 5,388 5,364 7,794 8,357 Operating loss (5,262 ) (2,913 ) (4,612 ) (3,311 ) Earnings from equity method investments 15,518 10,735 13,754 5,577 Royalties, related party 2,203 2,064 669 1,189 Other income (expenses), net 1,698 (1) 309 (1,852 ) 974 Income before income tax expense 14,157 10,195 7,959 4,429 Income tax (benefit) expense (61,673 ) (2) 583 99 53 Net income $ 75,830 $ 9,612 $ 7,860 $ 4,376 Earnings per common share – basic $ 3.45 $ 0.44 $ 0.36 $ 0.20 Earnings per common share – diluted $ 3.39 $ 0.43 $ 0.35 $ 0.20 Weighted-average number of common shares outstanding Basic 21,693 21,740 21,875 21,849 Diluted 22,061 22,098 22,187 22,177 (1) During the fourth quarter of 2016, the Company revised its estimate for future Royalty Award payments based on an updated forecast provided to the Company from Carbon Solutions. Based primarily on the updated forecast, the Company recorded a $4.0 million reduction to its Royalty Award accrual. (2) During the fourth quarter of 2016, the Company released $61.4 million of the valuation allowance related to the deferred tax assets that resulted in an income tax benefit of $61.7 million . See further discussion in Note 16. For the Quarter Ended (in thousands, except per share data) December 31, 2015 September 30, 2015 June 30, 2015 March 31, 2015 Revenues $ 13,202 $ 12,885 $ 14,895 $ 21,757 Cost of revenues, exclusive of operating expenses shown below 7,224 10,610 14,003 15,715 Other operating expenses 13,113 12,264 18,670 12,940 Operating loss (7,135 ) (9,989 ) (17,778 ) (6,898 ) Earnings (loss) from equity method investments 3,788 (41 ) 4,860 314 Royalties, related party 2,876 3,273 2,299 2,194 Other expenses, net (2,568 ) (1,853 ) (1,765 ) (1,698 ) Loss before income tax expense (3,039 ) (8,610 ) (12,384 ) (6,088 ) Income tax (benefit) expense (131 ) 44 63 44 Net loss $ (2,908 ) $ (8,654 ) $ (12,447 ) $ (6,132 ) Loss per common share – basic $ (0.13 ) $ (0.40 ) $ (0.57 ) $ (0.28 ) Loss per common share – diluted $ (0.13 ) $ (0.40 ) $ (0.57 ) $ (0.28 ) Weighted-average number of common shares outstanding Basic 21,676 21,687 21,715 21,696 Diluted 21,676 21,687 21,715 21,696

Summary of Operations and Sig26

Summary of Operations and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation	The Consolidated Financial Statements include accounts of wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. All investments in partially owned entities for which the Company has greater-than-20% ownership are accounted for using the equity method based on the legal form of the Company's ownership percentage and the applicable ownership percentage of the entity and are included in the Equity method investments line item in the Consolidated Balance Sheets . Tinuum Group is deemed to be variable interest entity ("VIE") under the VIE model of consolidation, but the Company does not consolidate Tinuum Group as it is not deemed to be its primary beneficiary.
Cash and Cash Equivalents and Restricted Cash	Cash and Cash Equivalents Cash and cash equivalents include bank deposits and other highly liquid investments purchased with an original maturity of three months or less. Restricted Cash Restricted cash primarily consists of funds withheld to provide collateral support for certain letters of credit issued to i) customers related to certain contractual performance and payment guarantees, ii) certain settlement parties to provide security for continuing royalty indemnification payments related to the settlement of certain litigation (the "Royalty Award"), and iii) minimum cash balance requirements under the 2013 Loan and Security Agreement ("Line of Credit").
Receivables and Credit Policies	Notes receivable are reported at their outstanding principal balances, adjusted for any amounts determined to be uncollectible. During the years ended December 31, 2015 and 2014 , the Company recorded impairment charges related to a Note Receivable of $0.5 million and $0.5 million , respectively, related to the write-off of a specific account whose ultimate collection was in doubt. Interest income is accrued and credited to income based on the unpaid principal balance outstanding. The accrual of interest is discontinued when substantial doubt exists about the ability to collect principal and interest based upon the contractual terms. Notes receivable are included within the Other assets line item in the Consolidated Balance Sheets . Receivable balances represent unsecured, customer obligations due under trade terms typically requiring payment within 30 - 45 days from the invoice date and are stated net of allowance for doubtful accounts. The Company records allowances for doubtful accounts when it is probable that the accounts receivable balances will not be collected.
Inventory	Inventories are stated at the lower of cost or market and consist principally of parts, components and materials for activated carbon injection ("ACI") and dry sorbent injection ("DSI") projects. The cost of inventory is determined using the first-in-first-out ("FIFO") method. Inventories are included within the Other assets line item in the Consolidated Balance Sheets .
Other Intangible Assets	Other Intangible assets consist of patents and licensed technology and are included in the Other assets line item in the Consolidated Balance Sheets . The Company has developed technologies resulting in patents being granted by the U.S. Patent and Trademark Office. All research and development costs associated with the technology development are expensed as incurred. Legal costs associated with securing the patent are capitalized and amortized over the legal or useful life beginning on the patent filing date.
Investment Securities	Investment securities represent certificates of deposits with original maturities greater than 90 days. Investment securities pledged as security for letters of credit in the same amount as the investments are classified as restricted in the accompanying Consolidated Balance Sheets and are carried at fair value. Investments in partially-owned subsidiaries for which the Company has less-than-20% ownership are accounted for using the cost method. Cost method investments are evaluated for impairment upon an indicator of impairment such as an event or change in circumstances that may have a significant adverse effect on the fair value of the investment. If no such events or changes in circumstances have occurred, the fair value is estimated only if practicable to do so.
Equity method of accounting	The investments in entities in which the Company does not have a controlling interest (financial or operating), but where it has the ability to exercise significant influence over operating and financial policies, are accounted for using equity-method accounting. Whether or not the Company exercises significant influence with respect to an investee depends on an evaluation of several factors including, among others, representation on the investee company’s board of directors and the Company's ownership level. Under the equity method of accounting, an investee company’s accounts are not reflected within the Company’s Consolidated Balance Sheets and Consolidated Statements of Operations ; however, the Company’s share of the earnings or losses of the investee company is reported in the Earnings from equity method investments line item in the Consolidated Statements of Operations and the Company’s carrying value in an equity method investee company is reported in the Equity method investments line in the Consolidated Balance Sheets . When the Company receives distributions in excess of the carrying value of the investment and the Company has not guaranteed any obligations of the investee, nor is it required to provide additional funding to the investee, the Company recognizes such excess distributions as equity method earnings in the period the distributions occur. When the investee subsequently reports income, the Company does not record its share of such income until it equals the amount of distributions in excess of carrying value that were previously recognized in income. During the years ended December 31, 2016 , 2015 and 2014 , the Company had no guarantees or requirements to provide additional funding to investees. Additionally, when the Company's carrying value in an equity method investment is zero and the Company has not guaranteed any obligations of the investee, nor is it required to provide additional funding to the investee, the Company will not recognize its share of any reported losses by the investee until future earnings are generated to offset previously unrecognized losses. As a result, equity income or loss reported on the Company's Consolidated Statements of Operations for certain equity method investment entities may differ from a mathematical calculation of net income or loss attributable to its equity interest based upon the percentage ownership of our equity interest and the net income or loss attributable to equity owners as shown on investee companies' statements of operations. Likewise, distributions from equity method investees are reported on the Consolidated Statements of Cash Flows as “return on investment” within Operating cash flows until such time as the carrying value in an equity method investee company is reduced to zero; thereafter, such distributions are reported as “distributions in excess of cumulative earnings” within Investing cash flows.
Royalties, related party	The Company licenses its M-45 TM and M-45-PC TM emission control technologies ("M-45 License") to Tinuum Group and realizes royalty income based upon
Property and Equipment	Property and equipment is stated at cost less accumulated depreciation and includes leasehold improvements. Depreciation on assets is computed using the straight-line method over the lesser of the estimated useful lives of the related assets or the lease term (ranging from 2 to 7 years). Maintenance and repairs which do not extend the useful life of the respective asset are charged to Operating expenses as incurred. When assets are retired, or otherwise disposed of, the property accounts are relieved of costs and accumulated depreciation and any resulting gain or loss is credited or charged to income. The Company performs an evaluation of the recoverability of the carrying value of its long-lived assets to determine if facts and circumstances indicate that the carrying value of assets may be impaired and if any adjustment is warranted.
Revenue Recognition	The Company recognizes revenues when: (i) persuasive evidence of a customer arrangement exists; (ii) the price is fixed or determinable; (iii) collectability is reasonable assured; and (iv) product delivery has occurred or services have been rendered and it is probable that performance guarantees, if any, will be met. Equipment sales The Company enters into contracts that require, over a period of months, the design and construction of emissions control systems ("extended equipment contracts"). Revenues from such extended equipment contracts are recorded using the percentage of completion cost to cost method based on costs incurred to date compared with total estimated contract costs. However, if the Company does not have sufficient information to estimate either costs incurred or total estimated costs for extended equipment contracts, the completed contract method is used. Under the completed contract method, revenues and costs from extended equipment contracts are deferred and recognized when contract obligations are substantially complete. The Company defines substantially complete as delivery of equipment and start-up at the customer site or, as applicable to DSI systems, the completion of any major warranty service period. Such costs are accumulated in the Costs in excess of billings on uncompleted contracts or Billings in excess of costs on uncompleted contracts line items in the Consolidated Balance Sheets , and typically include direct materials, direct labor and subcontractor costs, and indirect costs related to contract performance, such as indirect labor, supplies, tools and repairs. For each of the years ended December 31, 2016 , 2015 and 2014 , the Company did not have sufficient information to measure ongoing performance for its extended equipment contracts. Accordingly, the completed contract method of revenue recognition has been used for each of these years, and revenues and costs are deferred until the equipment is placed into service and contract obligations are substantially complete. When multiple contracts exist with a single counterparty, the Company evaluates revenue recognition on a contract-by-contract basis. Provisions for estimated losses on uncompleted contracts are recognized when it has been determined that a loss is probable. The Company also enters into other non-extended equipment contracts for which the Company recognizes revenues on a time and material basis as services to build equipment systems are performed or as equipment is delivered. Chemicals Revenues for direct sales of chemicals and other ancillary products not provided in the performance of construction of emissions control systems (extended equipment sales) are recognized at the date of delivery to, and acceptance by, the customer. Consulting services and other The Company recognizes revenues on time and material contracts as services are performed.
Cost of Revenues	Costs of revenue include all labor, fringe benefits, subcontract labor, chemical and coal costs, materials, equipment, supplies, travel costs and any other costs and expenses directly related to the Company’s production of revenues. The Company records estimated contract losses, if any, in the period they are determined.
Warranty Costs	Warranty costs for ACI equipment systems are estimated based on historical experience and are recorded as a percentage of revenue when the equipment is substantially complete. Warranty costs, comprised of the cost of replacement materials and direct labor, are included within the Equipment sales cost of revenue line in the Consolidated Statements of Operations . Warranty costs for DSI equipment systems could not be estimated at the time the contracts were entered into due to a lack of historical experience manufacturing DSI systems and the resulting claims history, if any, needed to determine an appropriate warranty amount. Therefore, revenue recognition on DSI equipment systems is deferred until the end of the warranty period, which is generally 12 to 24 months following substantial completion. As warranty claims are incurred, such costs are deferred within the Costs in excess of billings on uncompleted contracts line item in the Consolidated Balance Sheets , until such time that revenues and cost of revenue are recognized.
Expenses	Payroll and Benefits Payroll and benefits costs include direct payroll, personnel related fringe benefits, sales and administrative staff labor costs and stock compensation expense. Payroll and benefits costs exclude direct labor included in Cost of revenue. Rent and Occupancy Rent and occupancy costs include rent, insurance and other occupancy-related expenses. Legal and Professional Legal and professional costs include external legal, audit and consulting expenses. General and Administrative General and administrative costs include director fees and expenses, bad debt expense, impairments and other general costs of conducting business.
Research and Development Costs	Research and development costs are charged to expense in the period incurred. The Company has entered into development and cost-sharing contracts with the U.S. Department of Energy (the "DOE"). These contracts are best-effort-basis contracts, and the Company generally includes industry cost-share partners to offset the costs incurred that are anticipated to be in excess of funded amounts from the DOE. The Company accounts for these contracts with the DOE and industry cost-share partners in accordance with accounting guidance whereby the Company recognizes amounts funded by the DOE under research-and-development-cost-sharing arrangements as an offset to the Company's aggregate research and development expense reported in the Research and development, net line in the Consolidated Statements of Operations .
Asset Retirement Obligations	The Company's asset retirement obligation, or "ARO liability," consists of estimated costs to remove equipment and reclaim the land associated with one research and development project. The Company estimates its ARO liability for final reclamation based upon bids obtained from independent third parties and other exit alternatives, which are adjusted for inflation, and then discounted at a credit-adjusted risk-free rate. Changes in estimates could occur due to revisions of estimated costs and changes in timing and performance of the reclamation activities.
Income Taxes	The Company accounts for income taxes under the asset and liability method which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in operations in the period that includes the enactment date. The Company recognizes deferred tax assets and liabilities and maintains valuation allowances where it is more likely than not that all or a portion of deferred tax assets will not be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. The Company records uncertain tax positions on the basis of a two-step process whereby (1) the Company determines whether it is more-likely-than-not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company records interest expense due to the Company's share of Tinuum Group's equity method earnings for Refined Coal ("RC") facility leases which are treated as installment sales for tax purposes. IRS section 453A requires taxpayers using the installment method to pay an interest charge on the portion of the tax liability that is deferred under the installment method. The Company recognizes IRS section 453A interest ("453A interest") and other interest and penalties related to unrecognized tax benefits in the Interest expense line item in the Consolidated Statements of Operations .
Stock-Based Compensation	Stock-based compensation expense is measured at the grant date based on the estimated fair value of the stock-based award and expensed on a straight-line basis over the requisite service period for the entire award. Forfeitures are recognized when incurred. These costs are recorded in the Payroll and benefits line item in the Consolidated Statements of Operations .
Earnings (Loss) Per Share	earnings (loss) per share is computed using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for common stock and any participating securities according to dividend and participating rights in undistributed earnings. The Company's restricted stock awards ("RSA's") contain non-forfeitable rights to dividends or dividend equivalents and are deemed to be participating securities. The Company did not declare any cash dividends during the years ended December 31, 2016 , 2015 or 2014 . Under the two-class method, net income (loss) for the period is allocated between common stockholders and the holders of the participating securities based on the weighted-average of common shares outstanding during the period, excluding unvested RSA's ("common shares"), and the weighted-average number of unvested RSA's outstanding during the period, respectively. The allocated, undistributed income (loss) for the period is then divided by the weighted-average number of common shares and unvested RSA's outstanding during the period to arrive at basic earnings (loss) per common share and participating security for the period, respectively. Because the Company did not declare any dividends during the periods presented, and because the unvested RSA's possess substantially the same rights to undistributed earnings as common shares outstanding, there is no difference between the calculated basic earnings (loss) per share for common shares and participating securities. Accordingly, and pursuant to accounting principles generally accepted in the United States ("U.S. GAAP"), the Company has elected not to separately present basic or diluted earnings (loss) per share attributable to participating securities in the Consolidated Statements of Operations. Diluted earnings (loss) per share is computed in a manner consistent with that of basic earnings (loss) per shares, while considering other potentially dilutive securities. Potentially dilutive securities consist of outstanding options to purchase common stock and contingent performance stock units ("PSU's") (collectively, "Potential dilutive shares"), and their dilutive effect, if any, is computed using the treasury stock method. Potential dilutive shares are excluded from diluted earnings (loss) per share when their effect is anti-dilutive. When there is a net loss for a period, all Potential dilutive shares are anti-dilutive and are excluded from the calculation of diluted loss per share for that period. Each PSU represents a contingent right to receive shares of the Company’s common stock, and the number of shares may range from zero to two times the number of PSU's granted on the award date depending upon the price performance of the Company's common stock as measured against a general index and a specific peer group index over requisite performance periods. The number of Potential dilutive shares related to PSU's is based on the number of shares of the Company's common stock, if any, that would be issuable at the end of the respective reporting period, assuming that the end of the reporting period is the end of the contingency period applicable to such PSU's. See Note 13 for additional information related to PSU's. Potential dilutive shares were excluded in the diluted loss per share calculation for the year ended December 31, 2015 , as their inclusion was anti-dilutive due to the Company’s net loss for that year.
Use of Estimates	The preparation of the Company’s consolidated financial statements in conformity with U.S. GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. Actual results could differ from those estimates. The Company makes significant assumptions concerning: • revenue recognition, warranty estimates and performance guarantee accruals related to the Company's extended equipment contracts; • the impairment, or lack thereof, of the remaining realizability of, its long-lived assets; • stock compensation costs related to PSU and option awards; • estimated future royalty obligations associated with the Royalty Award and other legal accruals; and • the deferred tax assets expected to be realized in future periods and uncertain tax positions.
Reclassifications	Certain balances have been reclassified from prior years to conform to the current year presentation.
New Accounting Guidance	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASU 2014-09"), which provides a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific guidance. The core principle of ASU 2014-09 is that “an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 becomes effective for reporting periods (including interim periods) beginning after December 31, 2017. Early application is permitted for annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The standard may be applied retrospectively to each prior period presented or retrospectively with the cumulative effect recognized as of the date of adoption ("modified retrospective method"). The Company anticipates adopting the standard under the modified retrospective method effective January 1, 2018, which will be reflected in its financial statements as of and for the three months ended March 31, 2018. Based on the Company's preliminary assessment of the standard, the Company has determined that the timing of revenue recognition for equipment sales may be impacted, but that revenues generated from chemical sales and consulting services will likely not be impacted. The Company is continuing its assessment, which may change its initial assessments of the impacts to its revenue streams or may identify other impacts. In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements - Going Concern (Topic 205-40), Disclosure of Uncertainties about an Entities Ability to Continue as a Going Concern that requires management to evaluate whether there are conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern within one year after the date that the entity’s financial statements are issued, or within one year after the date the entity’s financial statements are available to be issued, and to provide disclosures when certain criteria are met. This guidance is effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The Company adopted this provision as of December 31, 2016 and there was no impact to the Company's financial statements or disclosures from the adoption of this standard. In November 2015, the FASB issued ASU 2015-17, Income Taxes (Topic 740) Balance Sheet Classification of Deferred Taxes ("ASU 2015-17"), to simplify the presentation of deferred income taxes. The amendments in ASU 2015-17 require that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. The current requirement that deferred tax liabilities and assets of a tax-paying component of an entity be offset and presented as a single amount is not affected by the amendments in the update. ASU 2015-17 is effective for fiscal years beginning after December 15, 2016, and interim periods within those years, and may be applied either prospectively to all deferred tax liabilities and assets or retrospectively to all periods presented. The Company adopted this standard effective as of January 1, 2016. There was no material impact to the Company's financial statements or disclosures from the adoption of this standard. In January 2016, the FASB issued ASU 2016-01, Financial Instruments (Subtopic 825-10) - Overall: Recognition and Measurement of Financial Assets and Financial Liabilities ("ASU 2016-01"). This standard provides guidance on how entities measure certain equity investments and present changes in the fair value. This standard requires that entities measure certain equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and recognize any changes in fair value in net income. ASU 2016-01 is effective for fiscal years beginning after December 31, 2017. The Company is currently evaluating the provisions of this guidance and assessing its impact on the Company's financial statements and disclosures. The Company does not believe this standard will have a material impact on the Company's financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) ("ASU 2016-02"), which requires lessees to recognize a right of use asset and related lease liability for those leases classified as operating leases at the commencement date and have lease terms of more than 12 months. This topic retains the distinction between finance leases and operating leases. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those years, and must be applied under a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The Company is currently evaluating the provisions of this guidance and assessing its impact on the Company's financial statements and disclosures. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"). The main objective of ASU 2016-13 is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. To achieve this objective, the amendments in ASU 2016-13 replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. ASU 2016-13 is effective for fiscal years beginning after December 15, 2019, including interim periods within those years, and must be adopted under a modified retrospective method approach. Entities may adopt ASU 2016-13 earlier as of the fiscal years beginning after December 15, 2018, including interim periods within those years. The Company is currently evaluating the provisions of this guidance and assessing its impact on the Company's financial statements and disclosures. The Company does not believe this standard will have a material impact on the Company's financial statements and disclosures. In October 2016, the FASB issued ASU 2016-17, Consolidation (Topic 810) Interests Held through Related Parties That Are under Common Control ("ASU 2016-17"), which amends the consolidation guidance on how a reporting entity that is the single decision maker of a VIE should treat indirect interests in the entity held through related parties that are under common control with the reporting entity when determining whether it is the primary beneficiary of that VIE. Under the amendments, a single decision maker is not required to consider indirect interests held through related parties that are under common control with the single decision maker to be the equivalent of direct interests in their entirety. Instead, a single decision maker is required to include those interests on a proportionate basis consistent with indirect interests held through other related parties. ASU 2016-17 is effective for fiscal years, and interim reporting periods within those years, beginning after December 15, 2016 on a retrospective basis, however, early adoption is permitted. The Company intends to adopt this standard effective as of January 1, 2017 and does not anticipate that the adoption will have a material impact on the Company's financial statements or disclosures. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230) Restricted Cash ("ASC 2016-18"), which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for fiscal years, and interim reporting periods within those years, beginning after December 15, 2017 on a retrospective basis, however, early adoption is permitted. The Company adopted this standard effective as of December 31, 2016. Therefore, the Consolidated Statements of Cash Flows for the years ended December 31, 2015 and 2014 were recast for the adoption of ASU 2016-18.
Fair Value of Financial Instruments	The carrying amounts of financial instruments, including cash and cash equivalents, accounts receivable, accounts payable, deposits and accrued expenses, approximate fair value due to the short maturity of these instruments. The estimated fair values of investment securities are described below. Refer to Note 4 for additional information regarding the Company’s investment securities. Fair value is defined as the price that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. The Company uses the hierarchy prescribed in the accounting guidance for fair value measurements, based upon the available inputs to the valuation and the degree to which they are observable or not observable in the market. The three levels in the hierarchy are as follows: • Level 1 Inputs - Quoted prices (unadjusted) for identical assets or liabilities in active markets that are accessible as of the measurement date. • Level 2 Inputs - Inputs other than quoted prices within Level 1 that are observable either directly or indirectly, including but not limited to, quoted prices in markets that are not active, quoted prices in active markets for similar assets or liabilities and observable inputs other than quoted prices such as interest rates or yield curves. • Level 3 Inputs - Unobservable inputs reflecting the Company’s own assumptions about the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk. The estimated fair value of certificates of deposit investments securities were estimated to be equal to the deposit value of the investment due to the market interest rates and relative short term nature of the instrument. The Company's experience with these types of investments and the expectations of the current investments held is that they will be satisfied at the current carrying amount. These securities were classified as Level 2.
Concentration of Credit Risk	Concentration of credit risk The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents and restricted cash. The Company holds such financial instruments at two financial institutions as of December 31, 2016. If those institutions were to be unable to perform their obligations, the Company would be at risk regarding the amount of investment in excess of the federal deposit insurance corporation limits ( $250 thousand ) that would be returned to the Company.
Segment Reporting	Corporate general and administrative expenses include certain costs that benefit the business as a whole but are not directly related to one of our segments. Such costs include but are not limited to accounting and human resources staff, information systems costs, legal fees, facility costs, audit fees and corporate governance expenses. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by a company's chief operating decision maker ("CODM"), or a decision making group, in deciding how to allocate resources and in assessing financial performance. As of December 31, 2016 , the Company's CODM was the Company's CEO. The Company's operating and reportable segments are organized by products and services provided. As of December 31, 2016, the Company has two reportable segments: (1) Refined Coal ("RC"); and (2) Emissions Control ("EC"). The business segment measurements provided to and evaluated by the CODM are computed in accordance with the principles listed below: • The accounting policies of the operating segments are the same as those described in the summary of significant accounting policies except as described below. • Segment revenue includes the Company's equity method earnings and losses from the Company's equity method investments. Segment revenue also includes the Company's royalty earnings from Tinuum Group and income related to sales-type leases. • Segment operating income (loss) includes the Company's equity method earnings and losses from the Company's equity method investments, royalty earnings from Tinuum Group (including depreciation and amortization expense) and gains related to sales of equity method investments. However, segment operating income (loss) excludes Payroll and benefits , Rent and occupancy , Legal and professional fees , and General and administrative ("Corporate general and administrative expenses") unless otherwise specifically included, as the Company does not allocate those amounts between segments. • All items not included in operating income, except as noted below, are excluded from the RC and EC segments.

Summary of Operations and Sig27

Summary of Operations and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Receivables	The following tables show the receivables balances: As of December 31, (in thousands) 2016 2015 Receivables $ 4,289 $ 8,518 Other Receivables 4,559 — Less: Allowance for doubtful accounts (200 ) (157 ) Total $ 8,648 $ 8,361 As of December 31, (in thousands) 2016 2015 Receivables, related parties $ 1,934 $ 1,918 Total $ 1,934 $ 1,918
Schedule of Intangible Assets	Years Ended December 31, 2016 2015 (in thousands, except years) Weighted-Average Amortization Period (in years) Initial Cost Net of Accumulated Amortization Initial Cost Net of Accumulated Amortization Patents 16 $ 913 $ 696 $ 742 $ 581 Licensed technology 0 1,525 — 1,525 1,360 Total 16 $ 2,438 $ 696 $ 2,267 $ 1,941
Calculations of Basic and Diluted Earnings Per Share	The following table sets forth the calculations of basic and diluted earnings (loss) per common share: Years Ended December 31, (in thousands, except per share amounts) 2016 2015 2014 Net income (loss) $ 97,678 $ (30,141 ) $ 1,387 Less: Undistributed income (loss) allocated to participating securities 1,105 (275 ) 18 Income (loss) attributable to common stockholders $ 96,573 $ (29,866 ) $ 1,369 Basic weighted-average number of common shares outstanding 21,931 21,773 21,554 Add: dilutive effect of equity instruments 303 — 525 Diluted weighted-average number of common shares outstanding 22,234 21,773 22,079 Earnings (loss) per share - basic $ 4.40 $ (1.37 ) $ 0.06 Earnings (loss) per share - diluted $ 4.34 $ (1.37 ) $ 0.06
Schedule of Anti-dilutive Equity Instruments	The table below presents the number of Potential dilutive shares that were excluded from the calculation of diluted loss per share because their inclusion would have been anti-dilutive: Years Ended December 31, (share data in thousands) 2016 2015 2014 Stock options — 10 — Restricted stock awards — 163 — Performance share units — 182 — Total shares excluded from diluted shares outstanding — 355 —

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring and Related Costs	A summary of the net pretax charges incurred by segment is as follows: Pretax Charge (in thousands, except employee data) Approximate Number of Employees Refined Coal Emissions Control All Other and Corporate Total Year ended December 31, 2016 Restructuring charges 40 $ — $ 1,164 $ 881 $ 2,045 Changes in estimates — (210 ) (276 ) (486 ) Total pretax charge, net of reversals $ — $ 954 $ 605 $ 1,559 Year ended December 31, 2015 Restructuring charges 162 $ — $ 5,108 $ 5,264 $ 10,372 Changes in estimates — (10 ) (2 ) (12 ) Total pretax charge, net of reversals $ — $ 5,098 $ 5,262 $ 10,360 Year ended December 31, 2014 Restructuring charges 29 $ — $ 1,294 $ 2,209 $ 3,503 Total pretax charge, net of reversals $ — $ 1,294 $ 2,209 $ 3,503
Schedule of Restructuring Reserve by Type of Cost	The following table summarizes the Company's utilization of restructuring accruals for the years ended December 31, 2016 , 2015 and 2014 : (in thousands) Employee Severance Facility Closures Beginning accrual as of January 1, 2014 $ 29 $ — Expense provision (1) 3,503 — Cash payments and other (1) (1,842 ) — Change in estimates (1) — — Accrual as of December 31, 2014 1,690 — Expense provision (1) 8,498 2,650 Cash payments and other (1) (7,595 ) (1,873 ) Change in estimates (1) (12 ) — Accrual as of December 31, 2015 2,581 777 Expense provision (1) 2,045 — Cash payments and other (1) (3,898 ) (320 ) Change in estimates (1) (276 ) (210 ) Accrual as of December 31, 2016 $ 452 $ 247 (1) Included within the Expense provision and Cash payments and other line items in the above table is equity-based compensation of $0.4 million , $3.4 million and $1.0 million for the years ended December 31, 2016 , 2015 and 2014 , respectively, resulting from the accelerated vesting of modified equity-based compensation awards for certain terminated employees. Additionally, as discussed in Note 8 , due to restructuring activities the Company fully impaired the carrying value of certain assets, thereby recognizing net impairment expense in the amount of $1.9 million during the year ended December 31, 2015 .

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment	The carrying basis and accumulated depreciation of property and equipment at December 31, 2016 and 2015 are: Life in Years As of December 31, (in thousands) 2016 2015 Machinery and equipment 2-7 $ 1,634 $ 3,498 Leasehold improvements 5-7 1,244 2,172 Furniture and fixtures 5-7 777 927 3,655 6,597 Less accumulated depreciation and amortization (2,920 ) (4,557 ) Total property and equipment, net $ 735 $ 2,040

Costs and Billings on Uncompl30

Costs and Billings on Uncompleted Contracts (Tables)	12 Months Ended
	Dec. 31, 2016
Costs and Billings on Uncompleted Contracts [Abstract]
Schedule of Deferred Project Costs and Revenue	The below table shows the components of these items: As of December 31, (in thousands) 2016 2015 Costs incurred on uncompleted contracts (gross) $ 42,993 $ 72,581 Billings on uncompleted contracts (gross) (47,915 ) (80,152 ) $ (4,922 ) $ (7,571 ) Included in the accompanying balance sheets under the following captions (1) : Costs in excess of billings on uncompleted contracts $ 25 $ 2,137 Billings in excess of costs on uncompleted contracts (4,947 ) (9,708 ) $ (4,922 ) $ (7,571 ) (1) Amounts presented after netting of costs and billings on an individual contract basis.

Research and Development and 31

Research and Development and Government and Industry Funded Contracts (Tables)	12 Months Ended
	Dec. 31, 2016
Government and Industry Funded Contracts [Abstract]
Schedule of Government and Industry Funded Contracts	The following table shows the impact to Research and development expense amounts recognized in the Consolidated Statement of Operations: Years Ended December 31, (in thousands) 2016 2015 2014 Research and development expense $ 173 $ 6,737 $ 3,554 Less: DOE funding 821 1,375 1,756 Industry cost-share funding — — 277 Research and development expense, net $ (648 ) $ 5,362 $ 1,521

Equity Method Investments (Tabl

Equity Method Investments (Tables)	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	The following tables summarize the assets and liabilities and results of operations of RCM6 for balance sheet dates and periods ended in which the Company owned a 24.95% membership interest: As of December 31, (in thousands) 2016 2015 Current assets $ — $ 12,240 Non-current assets $ — $ 2,472 Current liabilities $ — $ 1,489 Non-current liabilities $ — $ 7,649 Equity $ — $ 5,574 January 1 - March 3, Year ended December 31, (in thousands) 2016 2015 2014 Gross loss $ (555 ) $ (7,877 ) $ (8,257 ) Operating, selling, general and administrative expenses 360 2,178 2,123 Loss from operations (915 ) (10,055 ) (10,380 ) Other expenses (52 ) (641 ) (666 ) Net loss $ (967 ) $ (10,696 ) $ (11,046 ) ADES equity loss from RCM6 $ (557 ) $ (4,568 ) $ (4,497 ) The following table details the components of the Company's respective earnings or loss from equity method investments included within the Earnings from equity method investments line item on the Consolidated Statements of Operations : Year ended December 31, (in thousands) 2016 2015 2014 Earnings from Tinuum Group $ 41,650 $ 8,651 $ 43,584 Earnings from Tinuum Services 4,491 4,838 3,625 Loss from RCM6 (557 ) (4,568 ) (4,497 ) Earnings from equity method investments $ 45,584 $ 8,921 $ 42,712 The following table details the components of additional cash investments related to the Company's respective equity method investments included within the Consolidated Statements of Cash Flows : Year ended December 31, (in thousands) 2016 2015 2014 Purchase of RCM6 interest from Tinuum Group $ — $ — $ 3,153 Contributions to RCM6 223 2,398 3,478 Purchase of and contributions to equity method investments $ 223 $ 2,398 $ 6,631 The following table details the components of the cash distributions from the Company's respective equity method investments included within the Consolidated Statements of Cash Flows . Distributions from equity method investees are reported on the Consolidated Statements of Cash Flows as “return on investment” within Operating cash flows until such time as the carrying value in an equity method investee company is reduced to zero; thereafter, such distributions are reported as “distributions in excess of cumulative earnings” within Investing cash flows. Year ended December 31, (in thousands) 2016 2015 2014 Distributions from equity method investees, return on investment Tinuum Group (1) $ 3,400 $ — $ — Tinuum Services $ 4,500 $ 5,019 $ 2,509 Included in Operating Cash Flows $ 7,900 $ 5,019 $ 2,509 Distributions from equity method investees in excess of cumulative earnings Tinuum Group $ 38,250 $ 8,651 $ 43,584 Included in Investing Cash Flows $ 38,250 $ 8,651 $ 43,584 (1) During the three months ended March 31, 2016, the Company's cumulative share of pro-rata Tinuum Group income exceeded the amount of its cumulative income recognized due to cash being distributed. As such, the Company recognized $3.4 million as "return on investment". The following table details the carrying value of the Company's respective equity method investments included within the Equity method investments line item on the Consolidated Balance Sheets and indicates the Company's maximum exposure to loss: As of December 31, (in thousands) 2016 2015 Equity method investment in Tinuum Group $ — $ — Equity method investment in Tinuum Services 3,959 3,968 Equity method investment in RCM6 — 13,264 Total equity method investments $ 3,959 $ 17,232 The following tables summarize the assets, liabilities and results of operations of Tinuum Group: As of December 31, (in thousands) 2016 2015 Current assets $ 24,584 $ 40,860 Non-current assets $ 83,621 $ 90,725 Current liabilities $ 43,117 $ 60,987 Non-current liabilities $ 11,456 $ 9,412 Redeemable Class B equity $ 18,250 $ 30,448 Members deficit attributable to Class A members $ 26,475 $ 25,175 Noncontrolling interests $ 8,907 $ 5,563 Years Ended December 31, (in thousands) 2016 2015 2014 Gross profit $ 92,305 $ 108,416 $ 89,098 Operating, selling, general and administrative expenses 23,662 23,405 21,501 Income from operations 68,643 85,011 67,597 Other expenses (8,775 ) (2,203 ) (1,830 ) Class B preferred return (3,901 ) (6,157 ) (8,707 ) Loss attributable to noncontrolling interest 27,234 10,675 11,023 Net income available to Class A members $ 83,201 $ 87,326 $ 68,083 ADES equity earnings from Tinuum Group $ 41,650 $ 8,651 $ 43,584 The following tables summarize the assets, liabilities and results of operations of Tinuum Services: As of December 31, (in thousands) 2016 2015 Current assets $ 278,001 $ 186,959 Non-current assets $ 3,426 $ 3,704 Current liabilities $ 97,093 $ 92,675 Non-current liabilities $ 1,488 $ 1,366 Equity $ 7,918 $ 7,935 Noncontrolling interests $ 174,928 $ 88,687 Years Ended December 31, (in thousands) 2016 2015 2014 Gross loss $ (54,644 ) $ (42,496 ) $ (22,168 ) Operating, selling, general and administrative expenses 134,782 161,456 102,757 Loss from operations (189,426 ) (203,952 ) (124,925 ) Other expenses (56 ) (118 ) (62 ) Loss attributable to noncontrolling interest 198,464 213,746 132,237 Net income $ 8,982 $ 9,676 $ 7,250 ADES equity earnings from Tinuum Services $ 4,491 $ 4,838 $ 3,625 The following table presents the Company's investment balance, equity earnings and cash distributions in excess of the investment balance for the years ended December 31, 2014 through December 31, 2016 ( in thousands ): Description Date(s) Investment balance ADES equity earnings (loss) Cash distributions Memorandum Account: Cash distributions and equity loss in (excess) of investment balance Beginning balance 12/31/2013 $ — $ — $ — $ (12,906 ) ADES proportionate share of net income from Tinuum Group (1) 2014 activity 26,613 26,613 — — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2014 activity (12,906 ) (12,906 ) — 12,906 Cash distributions from Tinuum Group 2014 activity (43,584 ) — 43,584 — Adjustment for current year cash distributions in excess of investment balance 2014 activity 29,877 29,877 — (29,877 ) Total investment balance, equity earnings (loss) and cash distributions 12/31/2014 $ — $ 43,584 $ 43,584 $ (29,877 ) ADES proportionate share of net income from Tinuum Group (1) 2015 activity $ 35,265 $ 35,265 $ — $ — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2015 activity (29,877 ) (29,877 ) — 29,877 Cash distributions from Tinuum Group 2015 activity (8,651 ) — 8,651 — Adjustment for current year cash distributions in excess of investment balance 2015 activity 3,263 3,263 — (3,263 ) Total investment balance, equity earnings (loss) and cash distributions 12/31/2015 $ — $ 8,651 $ 8,651 $ (3,263 ) ADES proportionate share of net income from Tinuum Group (1) 2016 activity $ 35,019 $ 35,019 $ — $ — Recovery of cash distributions in excess of investment balance (prior to cash distributions) 2016 activity (3,263 ) (3,263 ) — 3,263 Cash distributions from Tinuum Group 2016 activity (41,650 ) — 41,650 — Adjustment for current year cash distributions in excess of investment balance 2016 activity 9,894 9,894 — (9,894 ) Total investment balance, equity earnings and cash distributions 12/31/2016 $ — $ 41,650 $ 41,650 $ (9,894 ) (1) The amounts of the Company's 42.5% proportionate share of net income as shown in the table above differ from mathematical calculations of the Company’s 42.5% equity interest in Tinuum Group multiplied by the amounts of Net Income available to Class A members as shown in the table above of Tinuum Group's results of operations due to adjustments related to the Class B preferred return and the elimination of Tinuum Group's earnings attributable to RCM6, of which the Company owned 24.95% during the years ended December 31, 2015 and 2014 and for the period from January 1 through March 3, 2016. As noted below, the Company sold its interest in RCM6 on March 3, 2016.

Acquisition (Tables)

Acquisition (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Summary of Purchase Consideration and Allocation	A summary of the purchase consideration and allocation of the purchase consideration is as follows: (in thousands) Purchase consideration: Cash paid $ 2,360 Fair value of liabilities assumed: Accrued liabilities 10 Contingent consideration 451 Total fair value of liabilities assumed 461 Total purchase consideration $ 2,821 Allocation of purchase consideration Receivables $ 360 Property and equipment and other 82 Intangibles - in process research and development 2,379 Total $ 2,821

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	The following table shows the other income recognized with related parties during the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, (in thousands) 2016 2015 2014 Royalties, related party - Tinuum Group $ 6,125 $ 10,642 $ 6,410 The following table summarizes the Company's notes payable (net of debt discount and issuance costs) classified according to payment terms, all of which are with related parties: As of December 31, (in thousands) Related Party 2016 2015 Short-term note payable Credit Agreement, net of discount Franklin Mutual $ — $ 12,676 Total Short-term borrowings — 12,676 Current portion of long-term borrowings RCM6 note payable, net of discount Tinuum Group — 1,207 DSI Business Owner note payable DSI Business Owner — 630 Total Current portion of long-term borrowings — 1,837 Total Short-term and current portion of long-term borrowings — 14,513 Long-term borrowings RCM6 note payable, net of discount Tinuum Group — 13,023 DSI Business Owner note payable DSI Business Owner — 489 Total Long-term borrowings — 13,512 Total Borrowings $ — $ 28,025 The following table shows the Company's payable balance associated with related parties, exclusive of amounts owed to employees and directors in the normal course of business, as of December 31, 2016 and 2015 , respectively: As of December 31, (in thousands) 2016 2015 Payable to related party - RCM6 $ — $ 270 The following table shows the revenues recognized with related parties during the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, (in thousands) 2016 2015 2014 Revenues from related party - Tinuum Group $ — $ 55 $ 665 The following table shows the Company's receivable balance associated with related parties as of December 31, 2016 and 2015 , respectively: As of December 31, (in thousands) 2016 2015 Receivable from related party - Tinuum Group $ 1,934 $ 1,918

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Schedule of Estimated Fair Values of Remaining Financial Instruments	The following table provides the estimated fair values of the remaining financial instruments: As of December 31, 2016 As of December 31, 2015 (in thousands) Carrying Value Fair Value Carrying Value Fair Value Financial Instruments: Investment securities: Investment securities, restricted, long-term $ — $ — $ 336 $ 336 Cost method investment $ 1,016 $ 1,016 $ 2,776 $ 2,776 Borrowings and Notes Payable Short-term borrowings, net of discount and deferred loan costs, related party $ — $ — $ 12,676 $ 12,676 Current portion of notes payable, related parties (1) $ — $ — $ 1,837 $ 1,457 Long-term portion of notes payable, related parties $ — $ — $ 13,512 $ 13,273 Highview technology license payable $ 207 $ 207 $ 519 $ 519 Highview technology license payable, long-term $ — $ — $ 1,038 $ 1,038 Stock appreciation rights, liability-classified equity award $ — $ — $ 742 $ 742 (1) The fair value related to the DSI business owner note payable amounts as of December 31, 2015 was determined using the settlement agreement amount of $0.3 million , as described in Note 9 .
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Financial instruments carried and measured at fair value on a recurring basis are presented in the table below according to the fair value hierarchy described above. There were no financial instruments carried and measured at fair value on a recurring basis as of December 31, 2016. As of December 31, 2015 Fair Value Measurement Using (in thousands) Level 1 Level 2 Level 3 Fair Value Assets: Investment securities, restricted, long-term $ — $ 336 $ — $ 336 Total assets at fair value $ — $ 336 $ — $ 336 Liabilities: Stock appreciation rights, liability-classified equity award $ — $ 742 $ — $ 742 Total liabilities at fair value $ — $ 742 $ — $ 742

Supplemental Financial Inform36

Supplemental Financial Information (Tables)	12 Months Ended
	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Prepaid Expenses and Other Assets and Other assets	The following table summarizes the components of Prepaid expenses and other assets and Other assets as presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Other current assets: Prepaid expenses $ 1,169 $ 2,117 Inventory 16 189 Other 172 — $ 1,357 $ 2,306 Other long-term assets: Deposits $ 263 $ 414 Intangibles 696 1,941 Other long-term assets 323 341 $ 1,282 $ 2,696
Schedule of Other Liabilities	The following table details the components of Other current liabilities and Other long-term liabilities as presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Other current liabilities: Accrued consultant incentives $ — $ 369 Accrued interest 618 1,042 Accrued losses on equipment contracts 183 759 Taxes payable 244 521 Deferred revenue 76 682 Warranty liabilities 287 1,197 Deferred rent 369 — Asset retirement obligation 1,312 1,248 Other 928 1,577 $ 4,017 $ 7,395 Other long-term liabilities: Deferred rent $ 38 $ 767 Advance deposit, related party — 2,981 Deferred revenue, related party 2,000 2,000 Other long-term liabilities — 2,604 $ 2,038 $ 8,352
Schedule of Warranty Obligations	The changes in the carrying amount of the Company’s warranty obligations, which do not include amounts for DSI systems, as revenues are deferred until the end of the warranty period, were as follows: As of December 31, (in thousands) 2016 2015 Balance, beginning of year $ 1,197 $ 152 Warranties accrued, net 89 1,337 Warranty claims (899 ) (292 ) Change in estimate related to previous warranties accrued (100 ) — Balance, end of year $ 287 $ 1,197
Schedule of Change in Asset Retirement Obligation	Included within Other current liabilities is the Company's asset retirement obligation. Changes in the Company's asset retirement obligations were as follows: As of December 31, (in thousands) 2016 2015 Asset retirement obligation, beginning of year $ 1,248 $ 1,188 Accretion 64 60 Asset retirement obligations, end of year $ 1,312 $ 1,248
Schedule of Statement of Operations, Supplemental Disclosures	The following table details the components of Interest expense in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 453A interest $ 2,490 $ 4,639 $ 3,371 Interest on RCM6 note payable, related party 263 2,468 2,245 Credit agreement interest 1,884 1,180 — Other 429 115 109 $ 5,066 $ 8,402 $ 5,725 The following table details the components of Other in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 Gain on sale of equity method investment $ 2,078 $ — $ — Gain on settlement of note payable and licensed technology 1,019 — — Impairment of cost method investment (1,760 ) — — Gain on termination of sales-type lease 891 — — Other 235 494 26 2,463 494 26

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option Valuation Assumptions	The following table indicates the weighted-average assumptions that were used related to the awards granted for the years ended December 31, 2016 , 2015 and 2014 , respectively: Years Ended December 31, 2016 2015 2014 Stock options granted: Risk-free interest rate 1.3 % 1.8 % 1.6 % Dividend yield — % — % — % Volatility 78.8 % 74.5 % 80.4 % Expected term (in years) 2.6 5.0 5.0
Equity Instruments, Other than Options, Valuation Assumptions	The following table indicates the weighted-average assumptions that were used related to the awards granted for the year ended December 31, 2015 . No SAR's were granted during the year ended December 31, 2016 . Year ended December 31, 2015 SAR's granted: Risk-free interest rate 1.8 % Dividend yield — % Volatility 74.5 % Expected term (in years) 5.0 PSU's - Compensation expense is recognized for PSU awards on a straight-line basis over a 3 -year service period based on the estimated fair value at the date of grant using a Monte Carlo simulation model. The following table indicates the weighted-average assumptions that were used related to the awards granted for the years ended December 31, 2015 and 2014 . No PSU's were granted during the year ended December 31, 2016 . Years Ended December 31, 2015 2014 PSUs granted: Risk-free interest rate 1.0 % 0.8 % Dividend yield — % — % Volatility 64.3 % 74.5 % Performance period (in years) 3.0 3.0
Allocation of Compensation Expense	The Company recorded the following compensation expense related to the Stock Plans: Years Ended December 31, (in thousands) 2016 2015 2014 RSA expense $ 2,021 $ 2,909 $ 2,612 Stock option expense 285 658 117 SAR expense 106 742 — PSU expense 456 2,895 1,983 Total stock-based compensation expense (1) 2,868 7,204 4,712 (1) Amounts for the years ended December 31, 2016 , 2015 and 2014 do not reflect an income tax benefit as a result of a valuation allowance on the Company's deferred tax assets.
Schedule of Unrecognized Compensation Cost	The amount of unrecognized compensation cost as of December 31, 2016 , and the expected weighted-average period over which the cost will be recognized is as follows: As of December 31, 2016 (in thousands) Unrecognized Compensation Cost Expected Weighted-Average Period of Recognition (in years) RSA expense $ 1,335 0.98 Stock option expense 732 0.53 PSU expense 137 0.63 Total unrecognized stock-based compensation expense $ 2,204 0.81
Summary of Restricted Stock Activity	A summary of the status and activity of non-vested RSA's is presented in the following table: For the Years Ended December 31. 2016 2015 2014 (in thousands, except for share and per share amounts) Shares Weighted- Shares Weighted-Average Shares Weighted-Average Non-vested at beginning of year 134,708 $ 8.49 209,921 $ 13.59 263,989 $ 9.05 Granted 363,758 $ 7.46 127,943 $ 14.97 112,643 $ 24.74 Vested (175,956 ) $ 11.96 (165,796 ) $ 17.51 (118,364 ) $ 15.75 Forfeited (1) (25,163 ) $ 15.58 (37,360 ) $ 19.30 (48,347 ) $ 9.49 Non-vested at end of year 297,347 $ 8.03 134,708 $ 8.49 209,921 $ 13.59
Summary of Option Activity	A summary of option activity under the Plans is presented below: (in thousands, except for share and per share amounts) Number of Weighted- Aggregate Intrinsic Value Weighted- For the year ended December 31, 2014 Options outstanding, January 1, 2014 317,576 $ 5.07 Options granted 30,000 $ 20.67 Options exercised (260,126 ) $ 4.30 Options expired / forfeited (13,250 ) $ 6.90 Options outstanding, December 31, 2014 74,200 $ 13.76 $ 670 3.0 Options vested and exercisable as of December 31, 2014 34,199 $ 8.44 $ 491 1.6 For the year ended December 31, 2015 Options outstanding, January 1, 2015 74,200 $ 13.76 Options granted 56,250 $ 13.87 Options exercised — $ — Options expired / forfeited (24,200 ) $ 7.59 Options outstanding, December 31, 2015 106,250 $ 15.22 $ — 3.8 Options vested and exercisable as of December 31, 2015 82,915 $ 14.04 $ — 3.9 For the year ended December 31, 2016 Options outstanding, January 1, 2016 106,250 $ 15.22 Options granted (1) 546,196 $ 11.10 Options exercised — $ — Options expired / forfeited (20,000 ) $ 16.90 Options outstanding, December 31, 2016 632,446 $ 11.61 $ 183 4.0 Options vested and exercisable as of December 31, 2016 247,780 $ 13.30 $ 69 3.4 (1) Included in options granted are 243,750 awards granted that were initially granted on a contingent basis and became exercisable as a result of the automatic expiration of the same number of Stock Appreciation Rights, as a result of stockholder approval of Amendment No. 4 of the 2007 Plan. See "Stock Appreciation Rights" section below for a discussion of the provisions of the exchange and incremental expense recognized.
Schedule of Equity Instruments, Other than Options Activity	A summary of SAR activity under the Plans is presented below: (in thousands, except for share and per share amounts) Number of Weighted- Aggregate Intrinsic Value Weighted- For the year ended December 31, 2015 SAR's outstanding as of January 1, 2015 — $ — Granted 243,750 $ 13.87 Exercised — $ — Expired / forfeited — $ — SAR's outstanding as of December 31, 2015 243,750 $ 13.87 $ — 4.5 SAR's vested and exercisable as of December 31, 2015 43,750 $ 13.87 $ — — For the year ended December 31, 2016 SAR's outstanding as of January 1, 2016 243,750 $ 13.87 Granted — $ — Exercised — $ — Expired / forfeited (243,750 ) $ 13.87 SAR's outstanding as of December 31, 2016 — $ — $ — — SAR's vested and exercisable as of December 31, 2016 — $ — $ — — A summary of the status and activity of non-vested PSU's is presented in the following table: For the Years Ended December 31. 2016 2015 2014 (in thousands, except for share and per share amounts) Units Weighted-Average Units Weighted-Average Units Weighted-Average Non-vested at beginning of year 169,334 $ 26.38 142,357 $ 30.65 89,578 $ 26.04 Granted (1) — $ — 69,218 $ 20.10 57,547 $ 37.45 Vested (1) (119,818 ) $ 26.87 (13,763 ) $ 30.52 — $ — Forfeited / Canceled (1) (2) — $ — (28,478 ) $ 30.44 (4,768 ) $ 26.04 Non-vested at end of year 49,516 $ 25.20 169,334 $ 26.38 142,357 $ 30.65 (1) The number of units shown in the table above are based on target performance. The final number of shares of common stock issued may vary depending on the achievement of market conditions established within the awards, which could result in the actual number of shares issued ranging from zero to a maximum of two times the number of units shown in the above table. (2) Included within the 2015 forfeited / canceled units are PSU's related to a former executive that were clawed back. The Company recognized $0.2 million within Other Income line item on the Consolidated Statement of Operations related to these awards .
Schedule of Performance-Based Units, Settled	The following table shows the PSUs that were settled by issuing the Company's common stock relative to a peer group performance index and broad stock index. Year of Grant Net Number of Issued Shares upon Vesting Shares Withheld to Settle Tax Withholding Obligations TSR Multiple Range Russell 3000 Multiple Low High Low High For the year ended December 31, 2016 2013 38,706 1,572 0.63 1.00 — — 2014 11,487 — 0.63 0.63 — — 2015 13,529 — 0.50 0.50 — — For the year ended December 31, 2015 2013 8,768 3,954 1.75 1.75 2.00 2.00 2014 2,506 1,145 0.63 0.75 — 0.75

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Settlement and Royalty Indemnity Obligation	The following table summarizes the Company's legal settlements and accruals as described above, which are presented in the Consolidated Balance Sheets : As of December 31, (in thousands) 2016 2015 Settlement and Royalty Indemnification $ 5,656 $ 6,502 Legal settlements 5,050 — Legal settlements and accruals, current 10,706 6,502 Settlement and Royalty Indemnification, long-term 5,382 13,797 Total legal settlements and accruals $ 16,088 $ 20,299
Schedule of Debt	The following tables summarize the LOC outstanding and related collateral reported in the Consolidated Balance Sheets : As of December 31, 2016 (in thousands) LOC Outstanding Utilization of LOC Availability Restricted Cash Restricted cash, long-term Investment securities, restricted, long-term Contract performance - equipment systems $ 1,855 $ 1,776 $ 86 $ — $ — Royalty award 7,150 — 7,150 — — Other 6,500 — 6,500 — — Total LOC outstanding $ 15,505 $ 1,776 $ 13,736 $ — $ — As of December 31, 2015 (in thousands) LOC Outstanding Utilization of LOC Availability Restricted Cash Restricted cash, long-term Investment securities, restricted, long-term Contract performance - equipment systems $ 5,556 — $ 728 $ 4,830 $ — Royalty award 6,150 — — 6,150 — Other 328 — — — 336 Total LOC outstanding $ 12,034 $ — $ 728 $ 10,980 $ 336
Schedule of Maturities of Long-term Debt	The following tables summarizes the expiration periods of the letters of credit based on the ultimate maturity date of the letters of credit as of December 31, 2016 : Expiration of Letters of Credit as of December 31, 2016 (in thousands) Less than 1 year 1-3 years 4-5 years After 5 years Letters of credit $ 10,855 $ 4,650 $ — $ —
Schedule of Future Minimum Rental Payments for Operating Leases	Annual minimum commitments under the leases as of December 31, 2016 are as follows: Years Ending December 31, Operating Lease Commitments (in thousands) 2017 $ 290 2018 268 2019 174 2020 55 Thereafter — Total $ 787
Schedule of Rent Expense	Rent expense incurred for the years ended are as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Rent expense $ 847 $ 1,838 $ 1,531

Defined Contributions Savings39

Defined Contributions Savings Plan (Tables)	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Schedule of Contributions and Recognized Expense	The following table presents the amount the Company recognized as expense within the Payroll and benefits line item in the Consolidated Statements of Operations : Years Ended December 31, (in thousands) 2016 2015 2014 401(k) employer expense $ 173 $ 439 $ 509

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Benefit (Expense) from Continuing Operations	The provision for income taxes consists of the following: Years Ended December 31, (in thousands, except for rate) 2016 2015 2014 Current portion of income tax expense (benefit): Federal $ — $ — $ — State 458 20 296 458 20 296 Deferred portion of income tax (benefit) expense: Federal (61,396 ) — — State — — — (61,396 ) — — Total income tax (benefit) expense $ (60,938 ) $ 20 $ 296 Effective tax rate (166 )% — % 18 %
Reconciliation of Expected Federal Income Taxes at Statutory Rates	A reconciliation of expected federal income taxes on income from operations at statutory rates with the expense (benefit) for income taxes is as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Federal statutory rate $ 12,859 $ (10,542 ) $ 589 State income taxes, net of federal benefit 987 (781 ) 31 Disallowed compensation — — 721 Permanent differences 84 35 52 Tax credits (2,419 ) (38,998 ) (25,607 ) Valuation allowances (72,359 ) 50,066 23,794 Changes in state effective rates (125 ) (243 ) 716 Stock-based compensation 36 487 — Other (1 ) (4 ) — (Benefit) expense for the provision for income taxes $ (60,938 ) $ 20 $ 296
Deferred Tax Assets And Liabilities	Details of the Company’s deferred tax assets and liabilities are summarized as follows: As of December 31, (in thousands) 2016 2015 Deferred tax assets Settlement and Royalty Indemnification $ 4,264 $ 7,807 Deferred revenues and loss contract provisions 268 2,899 Employee related liabilities 3,796 4,598 Intangible assets 1,518 1,733 Equity method investments 12,326 7,500 Net operating loss carryforward 13,341 23,193 Tax credits 99,903 97,484 Deposits on contracts — 1,146 Other 2,109 2,118 Total deferred tax assets 137,525 148,478 Less valuation allowance (75,910 ) (148,269 ) Deferred tax assets 61,615 209 Less: Deferred tax liabilities Property and equipment and other (219 ) (209 ) Total deferred tax liabilities (219 ) (209 ) Net deferred tax assets $ 61,396 $ —
Summary of Operating Loss Carryforwards and Tax Credit Carryforwards	The following table presents the approximate amount of federal and state net operating loss carryforwards and federal tax credit carryforwards available to reduce future taxable income, along with the respective range of years that the net operating loss and tax credit carryforwards would expire if not utilized: As of December 31, (in thousands) 2016 Beginning expiration year Ending expiration year Federal net operating loss carryforwards $ 31,699 2031 2036 State net operating loss carryforwards $ 57,600 2021 2036 Federal tax credit carryforwards $ 99,879 2031 2036
Schedule of Unrecognized Tax Benefits	The following table sets forth a reconciliation of the beginning and ending unrecognized tax benefits on a gross basis for the years ended December 31, 2016 , 2015 and 2014 : Years Ended December 31, (in thousands) 2016 2015 2014 Balance as of January 1 $ — $ — $ — Increases for tax positions of current year 54 — — Balance as of December 31 54 — —

Business Segment Information (T

Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment Operating Results	Years Ended December 31, (in thousands) 2016 2015 2014 Revenues: Refined Coal: Earnings in equity method investments $ 45,584 $ 8,921 $ 42,712 Consulting services — 55 665 Royalties, related party 6,125 10,642 6,410 51,709 19,618 49,787 Emissions Control: Equipment sales 46,949 60,099 12,044 Chemicals 3,025 888 391 Consulting services 648 1,697 3,823 50,622 62,684 16,258 Total segment reporting revenues $ 102,331 $ 82,302 $ 66,045 Adjustments to reconcile to reported revenues: Refined Coal: Earnings in equity method investments $ (45,584 ) $ (8,921 ) $ (42,712 ) Royalties, related party (6,125 ) (10,642 ) (6,410 ) (51,709 ) (19,563 ) (49,122 ) Total reported revenues $ 50,622 $ 62,739 $ 16,923 Segment reporting operating income (loss) Refined Coal (1) $ 51,264 $ 12,131 $ 42,094 Emissions Control (2) 7,334 (7,583 ) (13,348 ) Total segment operating income $ 58,598 $ 4,548 $ 28,746 (1) Included within the RC segment operating income for the year ended December 31, 2016 is a $2.1 million gain on the sale of RCM6 and for the years ended December 31, 2016 and 2015 , 453A interest expense of $2.5 million and $4.6 million , respectively, and interest expense related to the RCM6 note payable of $0.3 million and $2.5 million , respectively. (2) Included within the EC segment operating income for the year ended December 31, 2016 is a $0.9 million gain related to a termination of a sales-type lease.
Reconciliation of Reportable Segment Amounts to Consolidated Balances	A reconciliation of reportable segment income to the Company's consolidated net income is as follows: Years Ended December 31, (in thousands) 2016 2015 2014 Segment income Total reported segment operating income $ 58,598 $ 4,548 $ 28,746 Adjustments to reconcile to net income (loss) attributable to the Company Corporate payroll and benefits (9,415 ) (14,842 ) (12,621 ) Corporate rent and occupancy (1,187 ) (707 ) (694 ) Corporate legal and professional fees (8,230 ) (15,199 ) (9,514 ) Corporate general and administrative (3,811 ) (3,640 ) (3,980 ) Corporate depreciation and amortization (608 ) (578 ) (354 ) Corporate interest (expense) income, net (2,334 ) 24 74 Other income (expense), net 3,727 273 26 Income tax benefit (expense) 60,938 (20 ) (296 ) Net income (loss) $ 97,678 $ (30,141 ) $ 1,387
Reconciliation of Assets from Segment to Consolidated	Segment assets are as follows as of the dates presented: As of December 31, (in thousands) 2016 2015 Assets: Refined Coal $ 6,310 $ 19,507 Emissions Control 24,551 31,467 All Other and Corporate 76,435 9,801 Consolidated $ 107,296 $ 60,775

Major Customers (Tables)

Major Customers (Tables)	12 Months Ended
	Dec. 31, 2016
Major Customers Disclosure [Abstract]
Schedule of Sales by Major Customers	from unaffiliated customers who represent 10% or more of the Company’s revenues in any one year were as follows: Years Ended December 31, Customer Revenue Type Segment(s) 2016 2015 2014 A Equipment sales EC 21% 3% —% B Equipment sales, Consulting services EC 14% 16% 37% C Equipment sales, Consulting services, Other EC 1% 2% 24% D Consulting services EC —% 11% 8% E Equipment sales EC —% 15% —%

Quarterly Financial Results (43

Quarterly Financial Results (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	Summarized quarterly results for the two years ended December 31, 2016 and December 31, 2015 , respectively, are as follows: For the Quarter Ended (in thousands, except per share data) December 31, 2016 September 30, 2016 June 30, 2016 March 31, 2016 Revenues $ 3,604 $ 15,710 $ 8,951 $ 22,357 Cost of revenues, exclusive of operating expenses shown below 3,478 13,259 5,769 17,311 Other operating expenses 5,388 5,364 7,794 8,357 Operating loss (5,262 ) (2,913 ) (4,612 ) (3,311 ) Earnings from equity method investments 15,518 10,735 13,754 5,577 Royalties, related party 2,203 2,064 669 1,189 Other income (expenses), net 1,698 (1) 309 (1,852 ) 974 Income before income tax expense 14,157 10,195 7,959 4,429 Income tax (benefit) expense (61,673 ) (2) 583 99 53 Net income $ 75,830 $ 9,612 $ 7,860 $ 4,376 Earnings per common share – basic $ 3.45 $ 0.44 $ 0.36 $ 0.20 Earnings per common share – diluted $ 3.39 $ 0.43 $ 0.35 $ 0.20 Weighted-average number of common shares outstanding Basic 21,693 21,740 21,875 21,849 Diluted 22,061 22,098 22,187 22,177 (1) During the fourth quarter of 2016, the Company revised its estimate for future Royalty Award payments based on an updated forecast provided to the Company from Carbon Solutions. Based primarily on the updated forecast, the Company recorded a $4.0 million reduction to its Royalty Award accrual. (2) During the fourth quarter of 2016, the Company released $61.4 million of the valuation allowance related to the deferred tax assets that resulted in an income tax benefit of $61.7 million . See further discussion in Note 16. For the Quarter Ended (in thousands, except per share data) December 31, 2015 September 30, 2015 June 30, 2015 March 31, 2015 Revenues $ 13,202 $ 12,885 $ 14,895 $ 21,757 Cost of revenues, exclusive of operating expenses shown below 7,224 10,610 14,003 15,715 Other operating expenses 13,113 12,264 18,670 12,940 Operating loss (7,135 ) (9,989 ) (17,778 ) (6,898 ) Earnings (loss) from equity method investments 3,788 (41 ) 4,860 314 Royalties, related party 2,876 3,273 2,299 2,194 Other expenses, net (2,568 ) (1,853 ) (1,765 ) (1,698 ) Loss before income tax expense (3,039 ) (8,610 ) (12,384 ) (6,088 ) Income tax (benefit) expense (131 ) 44 63 44 Net loss $ (2,908 ) $ (8,654 ) $ (12,447 ) $ (6,132 ) Loss per common share – basic $ (0.13 ) $ (0.40 ) $ (0.57 ) $ (0.28 ) Loss per common share – diluted $ (0.13 ) $ (0.40 ) $ (0.57 ) $ (0.28 ) Weighted-average number of common shares outstanding Basic 21,676 21,687 21,715 21,696 Diluted 21,676 21,687 21,715 21,696

Summary of Operations and Sig44

Summary of Operations and Significant Accounting Policies - Narrative (Details) $ / shares in Units, $ in Thousands, £ in Millions	Mar. 14, 2014	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014USD ($)	Dec. 31, 2016GBP (£)shares	Jun. 15, 2016USD ($)	Jun. 15, 2016GBP (£)	Nov. 30, 2014	Jan. 20, 2010
Accounting Policies [Line Items]
Common stock authorized (in shares) | shares		100,000,000	100,000,000		100,000,000
Common stock par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Preferred stock authorized (in shares) | shares		50,000,000	50,000,000		50,000,000
Preferred stock par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Provision for debt expense		$ 0	$ 100	$ 0
Note receivable, impairment charges			500	500
Inventory		16	189
Gain on contract termination		891	0	0
Amortization expense		100	$ 400	$ 0
Estimated future amortization, year one		100
Estimated future amortization, year two		100
Estimated future amortization, year three		100
Estimated future amortization, year four		100
Estimated future amortization, year five		$ 100
Stock split, conversion ratio	2
Minimum
Accounting Policies [Line Items]
Accounts receivable payment terms		30 days
Property and equipment estimated useful lives		2 years
Warranty term		12 months
Maximum
Accounting Policies [Line Items]
Accounts receivable payment terms		45 days
Property and equipment estimated useful lives		7 years
Warranty term		24 months
Tinuum Group
Accounting Policies [Line Items]
Ownership interest, percent		42.50%	42.50%		42.50%
Tinuum Services
Accounting Policies [Line Items]
Ownership interest, percent		50.00%			50.00%				50.00%
Highview Enterprises Limited
Accounting Policies [Line Items]
Ownership interest, percent								8.00%
Highview Enterprises Limited | Licensed technology
Accounting Policies [Line Items]
Long-term licensing agreement, termination fee		$ 200			£ 0.2	$ 200	£ 0.2
Gain on contract termination		$ 200

Summary of Operations and Sig45

Summary of Operations and Significant Accounting Policies - Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounts Receivable, Net, Current [Abstract]
Receivables	$ 4,289	$ 8,518
Other Receivables	4,559	0
Less: Allowance for doubtful accounts	(200)	(157)
Total	8,648	8,361
Due from Related Parties, Current [Abstract]
Receivables, related parties	1,934	1,918
Total	$ 1,934	$ 1,918

Summary of Operations and Sig46

Summary of Operations and Significant Accounting Policies - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period (in years)	16 years
Initial Cost	$ 2,438	$ 2,267
Net of Accumulated Amortization	$ 696	1,941
Patents
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Amortization Period (in years)	16 years
Initial Cost	$ 913	742
Net of Accumulated Amortization	696	581
Licensed technology
Finite-Lived Intangible Assets [Line Items]
Initial Cost	1,525	1,525
Net of Accumulated Amortization	$ 0	$ 1,360

Summary of Operations and Sig47

Summary of Operations and Significant Accounting Policies - Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net income	$ 75,830	$ 9,612	$ 7,860	$ 4,376	$ (2,908)	$ (8,654)	$ (12,447)	$ (6,132)	$ 97,678	$ (30,141)	$ 1,387
Less: Undistributed income (loss) allocated to participating securities									1,105	(275)	18
Income (loss) attributable to common stockholders									$ 96,573	$ (29,866)	$ 1,369
Basic weighted-average number of common shares outstanding (in shares)	21,693	21,740	21,875	21,849	21,676	21,687	21,715	21,696	21,931	21,773	21,554
Add: dilutive effect of equity instruments (in shares)									303	0	525
Diluted weighted-average number of common shares outstanding (in shares)	22,061	22,098	22,187	22,177	21,676	21,687	21,715	21,696	22,234	21,773	22,079
Earnings (loss) per share - basic (in dollars per share)	$ 3.45	$ 0.44	$ 0.36	$ 0.20	$ (0.13)	$ (0.40)	$ (0.57)	$ (0.28)	$ 4.40	$ (1.37)	$ 0.06
Earnings (loss) per share - diluted (in dollars per share)	$ 3.39	$ 0.43	$ 0.35	$ 0.20	$ (0.13)	$ (0.40)	$ (0.57)	$ (0.28)	$ 4.34	$ (1.37)	$ 0.06

Summary of Operations and Sig48

Summary of Operations and Significant Accounting Policies - Anti-dilutive Equity Instruments (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares excluded from diluted shares outstanding (in shares)	0	355	0
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares excluded from diluted shares outstanding (in shares)	0	10	0
Restricted stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares excluded from diluted shares outstanding (in shares)	0	163	0
Performance share units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total shares excluded from diluted shares outstanding (in shares)	0	182	0

Restructuring - Net Pretax Bene

Restructuring - Net Pretax Benefits (Charges), Incurred by Segment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)employee	Dec. 31, 2015USD ($)employee	Dec. 31, 2014USD ($)employee
Restructuring Cost and Reserve [Line Items]
Approximate Number of Employees | employee	40	162	29
Restructuring charges	$ 2,045	$ 10,372	$ 3,503
Changes in estimates	(486)	(12)
Total pretax charge, net of reversals	1,559	10,360	3,503
All Other and Corporate
Restructuring Cost and Reserve [Line Items]
Restructuring charges	881	5,264	2,209
Changes in estimates	(276)	(2)
Total pretax charge, net of reversals	605	5,262	2,209
Refined Coal | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	0	0
Changes in estimates	0	0
Total pretax charge, net of reversals	0	0	0
Emissions Control | Operating Segments
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,164	5,108	1,294
Changes in estimates	(210)	(10)
Total pretax charge, net of reversals	$ 954	$ 5,098	$ 1,294

Restructuring - Utilization of

Restructuring - Utilization of Restructuring Accruals (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Reserve [Roll Forward]
Share-based compensation	$ 400	$ 3,400	$ 1,000
Asset impairment charges	520	2,087	355
ADA Analytics Israel, LLC
Restructuring Reserve [Roll Forward]
Asset impairment charges		1,900
Employee Severance
Restructuring Reserve [Roll Forward]
Accrual, Beginning balance	2,581	1,690	29
Expense provision	2,045	8,498	3,503
Cash payments and other	(3,898)	(7,595)	(1,842)
Change in estimates	(276)	(12)	0
Accrual, Ending balance	452	2,581	1,690
Facility Closures
Restructuring Reserve [Roll Forward]
Accrual, Beginning balance	777	0	0
Expense provision	0	2,650	0
Cash payments and other	(320)	(1,873)	0
Change in estimates	(210)	0	0
Accrual, Ending balance	$ 247	$ 777	$ 0

Property and Equipment (Details

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 3,655	$ 6,597
Less accumulated depreciation and amortization	(2,920)	(4,557)
Total property and equipment, net	$ 735	2,040
Minimum
Property, Plant and Equipment [Line Items]
Life in Years	2 years
Maximum
Property, Plant and Equipment [Line Items]
Life in Years	7 years
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 1,634	3,498
Machinery and equipment | Minimum
Property, Plant and Equipment [Line Items]
Life in Years	2 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Line Items]
Life in Years	7 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 1,244	2,172
Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Life in Years	5 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Life in Years	7 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 777	$ 927
Furniture and fixtures | Minimum
Property, Plant and Equipment [Line Items]
Life in Years	5 years
Furniture and fixtures | Maximum
Property, Plant and Equipment [Line Items]
Life in Years	7 years

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 900	$ 1,700	$ 1,800
Depreciation	200
Property and equipment	735	2,040
Proceeds from sale of property and equipment	52	942	26
Restructuring charges	2,045	10,372	$ 3,503
Facility Closures
Property, Plant and Equipment [Line Items]
Restructuring charges		800
Disposed of by Sale
Property, Plant and Equipment [Line Items]
Impairment charges	$ 500
Proceeds from sale of impaired assets		600
Property and equipment		100
Proceeds from sale of property and equipment		300
Gain on disposition of assets		200
Disposed of by Sale | General and Administrative Expense
Property, Plant and Equipment [Line Items]
Impairment charges		$ 300

Investments - Narrative (Detail

Investments - Narrative (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2014USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2016£ / shares	Jun. 30, 2016£ / shares
Investment [Line Items]
Share price (in gbp per share) | £ / shares						£ 4.25
Asset impairment charges			$ 520	$ 2,087	$ 355
Cost method investment
Investment [Line Items]
Available-for-sale securities, debt securities		$ 1,000	1,000	2,800
Highview Enterprises Limited
Investment [Line Items]
Ownership interest, percent	8.00%
Payments to acquire investments	$ 2,800
Highview Enterprises Limited | Cost method investment
Investment [Line Items]
Share price (in gbp per share) | £ / shares							£ 2
Highview Enterprises Limited | Cost method investment | Other
Investment [Line Items]
Asset impairment charges		1,800
Certificates of deposit
Investment [Line Items]
Investments		$ 0	$ 0	$ 300

Costs and Billings on Uncompl54

Costs and Billings on Uncompleted Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cost and Billings on Uncompleted Contracts [Line Items]
Costs incurred on uncompleted contracts (gross)	$ 42,993	$ 72,581
Billings on uncompleted contracts (gross)	(47,915)	(80,152)
Total deferred revenue	(4,922)	(7,571)
Costs in excess of billings on uncompleted contracts	25	2,137
Billings in excess of costs on uncompleted contracts	(4,947)	(9,708)
Provision for loss on uncompleted contracts	200	800
Other current liabilities
Cost and Billings on Uncompleted Contracts [Line Items]
Loss on contracts provisions	$ 400	$ 300	$ 300

Research and Development and 55

Research and Development and Government and Industry Funded Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Government and Industry Funded Contracts [Abstract]
Research and development expense	$ 173	$ 6,737	$ 3,554
DOE funding	821	1,375	1,756
Industry cost-share funding	0	0	277
Research and development expense, net	(648)	5,362	1,521
Business Acquisition [Line Items]
Asset impairment charges	$ 520	2,087	$ 355
ADA Analytics Israel, LLC
Business Acquisition [Line Items]
Asset impairment charges		$ 1,900

Equity Method Investments - Nar

Equity Method Investments - Narrative (Details) - USD ($)	Mar. 03, 2016	Mar. 03, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 10, 2014	Dec. 31, 2013	Jan. 20, 2010
Schedule of Equity Method Investments [Line Items]
Earnings from equity method investments			$ 15,518,000	$ 10,735,000	$ 13,754,000	$ 5,577,000	$ 3,788,000	$ (41,000)	$ 4,860,000	$ 314,000	$ 45,584,000	$ 8,921,000	$ 42,712,000
Equity method investments			3,959,000				17,232,000				3,959,000	17,232,000
Gain on sale of equity method investment											2,078,000	0	0
Purchase, contributions and advances to equity method investees											223,000	2,128,000	6,631,000
Purchase of membership interest, note payable outstanding			$ 0				$ 28,025,000				0	28,025,000
Impairment of equity method investments											$ 0	$ 0	0
Disposed of by Sale | RCM6, LLC (RCM6)
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent	24.95%	24.95%
Net sales proceeds, including proceeds received by third parties	$ 1,800,000
Tinuum Group
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent			42.50%				42.50%				42.50%	42.50%
Preferred return to third party unitholders											15.00%
Preferred unitholder, redemption period											10 years
Preferred unitholder, redemption notice period											180 days
Voting interest			50.00%								50.00%
Earnings from equity method investments											$ 41,650,000	$ 8,651,000	43,584,000
Equity method investments			$ 0				$ 0				0	0	0		$ 0
Losses related to VIEs, attributable to noncontrolling interest											27,234,000	10,675,000	11,023,000
Tinuum Group | Cash distributions
Schedule of Equity Method Investments [Line Items]
Earnings from equity method investments											(41,650,000)	(8,651,000)	(43,584,000)
Equity method investments			41,650,000				8,651,000				41,650,000	8,651,000	43,584,000		0
Tinuum Group | Memo Account: Cash distributions and equity loss in (excess) of investment balance
Schedule of Equity Method Investments [Line Items]
Earnings from equity method investments											0	0	0
Equity method investments			$ 9,894,000				(3,263,000)				$ 9,894,000	(3,263,000)	(29,877,000)		$ (12,906,000)
NexGen Refined Coal, LLC (NexGen)
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent			42.50%								42.50%
GSFS Investments I Corp. (GSFS)
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent			15.00%								15.00%
Tinuum Services
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent			50.00%								50.00%					50.00%
Earnings from equity method investments											$ 4,491,000	4,838,000	3,625,000
Equity method investments			$ 3,959,000				3,968,000				3,959,000	3,968,000
Losses related to VIEs, attributable to noncontrolling interest											$ 198,464,000	213,746,000	132,237,000
RCM6, LLC (RCM6)
Schedule of Equity Method Investments [Line Items]
Ownership interest, percent			24.95%								24.95%			24.95%
Earnings from equity method investments		$ (557,000)									$ (557,000)	(4,568,000)	(4,497,000)
Equity method investments			$ 0				13,264,000				0	13,264,000
Purchase, contributions and advances to equity method investees											200,000	2,400,000	4,200,000
Purchase of membership interest, note payable outstanding			14,200,000				$ 14,200,000				14,200,000	14,200,000
Amount by which investment exceeded proportionate share of investee's net assets			$ 11,900,000								11,900,000
Earnings (loss) from equity method investment for depreciation and amortization related to investment basis difference											300,000	$ 1,900,000	$ 1,700,000
RCM6, LLC (RCM6) | Refined Coal
Schedule of Equity Method Investments [Line Items]
Gain on sale of equity method investment											$ 2,100,000

Equity Method Investments - Equ

Equity Method Investments - Equity Method Investments (Details) - USD ($)	2 Months Ended	3 Months Ended								12 Months Ended
	Mar. 03, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
ADES equity earnings (loss)		$ 15,518,000	$ 10,735,000	$ 13,754,000	$ 5,577,000	$ 3,788,000	$ (41,000)	$ 4,860,000	$ 314,000	$ 45,584,000	$ 8,921,000	$ 42,712,000
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Equity method investments		3,959,000				17,232,000				3,959,000	17,232,000
Earnings from equity method investments		15,518,000	$ 10,735,000	$ 13,754,000	5,577,000	3,788,000	$ (41,000)	$ 4,860,000	$ 314,000	45,584,000	8,921,000	42,712,000
Purchase of and contributions to equity method investments										223,000	2,398,000	6,631,000
Distributions from equity method investees, return on investment										7,900,000	5,019,000	2,509,000
Included in Investing Cash Flows										38,250,000	8,651,000	43,584,000
Tinuum Group
Equity Method Investment, Summarized Financial Information [Abstract]
Current assets		24,584,000				40,860,000				24,584,000	40,860,000
Non-current assets		83,621,000				90,725,000				83,621,000	90,725,000
Current liabilities		43,117,000				60,987,000				43,117,000	60,987,000
Non-current liabilities		11,456,000				9,412,000				11,456,000	9,412,000
Redeemable Class B equity		18,250,000				30,448,000				18,250,000	30,448,000
Members deficit attributable to Class A members		26,475,000				25,175,000				26,475,000	25,175,000
Noncontrolling interests		8,907,000				5,563,000				8,907,000	5,563,000
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Gross profit										92,305,000	108,416,000	89,098,000
Operating, selling, general and administrative expenses										23,662,000	23,405,000	21,501,000
Income (loss) from operations										68,643,000	85,011,000	67,597,000
Other expenses										(8,775,000)	(2,203,000)	(1,830,000)
Class B preferred return										(3,901,000)	(6,157,000)	(8,707,000)
Loss attributable to noncontrolling interest										27,234,000	10,675,000	11,023,000
Net income (loss)										83,201,000	87,326,000	68,083,000
ADES equity earnings (loss)										41,650,000	8,651,000	43,584,000
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Equity method investments		0				0				0	0	0	$ 0
Earnings from equity method investments										41,650,000	8,651,000	43,584,000
Purchase of and contributions to equity method investments										0	0	3,153,000
Distributions from equity method investees, return on investment					$ 3,400,000					3,400,000	0	0
Distributions from equity method investees in excess of cumulative earnings										38,250,000	8,651,000	43,584,000
Included in Investing Cash Flows										9,894,000	3,263,000	29,877,000
Tinuum Services
Equity Method Investment, Summarized Financial Information [Abstract]
Current assets		278,001,000				186,959,000				278,001,000	186,959,000
Non-current assets		3,426,000				3,704,000				3,426,000	3,704,000
Current liabilities		97,093,000				92,675,000				97,093,000	92,675,000
Non-current liabilities		1,488,000				1,366,000				1,488,000	1,366,000
Equity		7,918,000				7,935,000				7,918,000	7,935,000
Noncontrolling interests		174,928,000				88,687,000				174,928,000	88,687,000
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Gross profit										(54,644,000)	(42,496,000)	(22,168,000)
Operating, selling, general and administrative expenses										134,782,000	161,456,000	102,757,000
Income (loss) from operations										(189,426,000)	(203,952,000)	(124,925,000)
Other expenses										(56,000)	(118,000)	(62,000)
Loss attributable to noncontrolling interest										198,464,000	213,746,000	132,237,000
Net income (loss)										8,982,000	9,676,000	7,250,000
ADES equity earnings (loss)										4,491,000	4,838,000	3,625,000
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Equity method investments		3,959,000				3,968,000				3,959,000	3,968,000
Earnings from equity method investments										4,491,000	4,838,000	3,625,000
Distributions from equity method investees, return on investment										4,500,000	5,019,000	2,509,000
RCM6, LLC (RCM6)
Equity Method Investment, Summarized Financial Information [Abstract]
Current assets		0				12,240,000				0	12,240,000
Non-current assets		0				2,472,000				0	2,472,000
Current liabilities		0				1,489,000				0	1,489,000
Non-current liabilities		0				7,649,000				0	7,649,000
Equity		0				5,574,000				0	5,574,000
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Gross profit	$ (555,000)										(7,877,000)	(8,257,000)
Operating, selling, general and administrative expenses	360,000										2,178,000	2,123,000
Income (loss) from operations	(915,000)										(10,055,000)	(10,380,000)
Other expenses	(52,000)										(641,000)	(666,000)
Net income (loss)	(967,000)										(10,696,000)	(11,046,000)
ADES equity earnings (loss)	(557,000)									(557,000)	(4,568,000)	(4,497,000)
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Equity method investments		$ 0				$ 13,264,000				0	13,264,000
Earnings from equity method investments	$ (557,000)									(557,000)	(4,568,000)	(4,497,000)
Purchase of and contributions to equity method investments										$ 223,000	$ 2,398,000	$ 3,478,000

Equity Method Investments - Rol

Equity Method Investments - Rollforward of CCS Investment (Details) - USD ($)	2 Months Ended	3 Months Ended								12 Months Ended
	Mar. 03, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 10, 2014
Equity Method Investments [Roll Forward]
Beginning balance	$ 17,232,000				$ 17,232,000					$ 17,232,000
Cash distributions from Tinuum Group		$ (15,518,000)	$ (10,735,000)	$ (13,754,000)	(5,577,000)	$ (3,788,000)	$ 41,000	$ (4,860,000)	$ (314,000)	(45,584,000)	$ (8,921,000)	$ (42,712,000)
Adjustment for current year cash distributions in excess of investment balance										38,250,000	8,651,000	43,584,000
Total investment balance, equity earnings (loss) and cash distributions		3,959,000				17,232,000				3,959,000	17,232,000
Tinuum Group
Equity Method Investments [Roll Forward]
Beginning balance	0				0				0	0	0	0
ADES proportionate share of income from CCS										35,019,000	35,265,000	26,613,000
Recovery of cash distributions in excess of investment balance (prior to cash distributions)										(3,263,000)	(29,877,000)	(12,906,000)
Cash distributions from Tinuum Group										(41,650,000)	(8,651,000)	(43,584,000)
Adjustment for current year cash distributions in excess of investment balance										9,894,000	3,263,000	29,877,000
Total investment balance, equity earnings (loss) and cash distributions		$ 0				$ 0				$ 0	$ 0	0
Ownership interest, percent		42.50%				42.50%				42.50%	42.50%
Ownership interest multiplied by net income available to members, percent		42.50%								42.50%
Tinuum Group | ADES equity earnings (loss)
Equity Method Investments [Roll Forward]
Beginning balance	8,651,000				8,651,000				43,584,000	$ 8,651,000	$ 43,584,000	0
ADES proportionate share of income from CCS										35,019,000	35,265,000	26,613,000
Recovery of cash distributions in excess of investment balance (prior to cash distributions)										(3,263,000)	(29,877,000)	(12,906,000)
Cash distributions from Tinuum Group										0	0	0
Adjustment for current year cash distributions in excess of investment balance										9,894,000	3,263,000	29,877,000
Total investment balance, equity earnings (loss) and cash distributions		$ 41,650,000				$ 8,651,000				41,650,000	8,651,000	43,584,000
Tinuum Group | Cash distributions
Equity Method Investments [Roll Forward]
Beginning balance	8,651,000				8,651,000				43,584,000	8,651,000	43,584,000	0
ADES proportionate share of income from CCS										0	0	0
Recovery of cash distributions in excess of investment balance (prior to cash distributions)										0	0	0
Cash distributions from Tinuum Group										41,650,000	8,651,000	43,584,000
Adjustment for current year cash distributions in excess of investment balance										0	0	0
Total investment balance, equity earnings (loss) and cash distributions		41,650,000				8,651,000				41,650,000	8,651,000	43,584,000
Tinuum Group | Memo Account: Cash distributions and equity loss in (excess) of investment balance
Equity Method Investments [Roll Forward]
Beginning balance	(3,263,000)				(3,263,000)				$ (29,877,000)	(3,263,000)	(29,877,000)	(12,906,000)
ADES proportionate share of income from CCS										0	0	0
Recovery of cash distributions in excess of investment balance (prior to cash distributions)										3,263,000	29,877,000	12,906,000
Cash distributions from Tinuum Group										0	0	0
Adjustment for current year cash distributions in excess of investment balance										(9,894,000)	(3,263,000)	(29,877,000)
Total investment balance, equity earnings (loss) and cash distributions		9,894,000				(3,263,000)				9,894,000	(3,263,000)	(29,877,000)
RCM6, LLC (RCM6)
Equity Method Investments [Roll Forward]
Beginning balance	13,264,000				$ 13,264,000					13,264,000
Cash distributions from Tinuum Group	$ 557,000									557,000	4,568,000	$ 4,497,000
Total investment balance, equity earnings (loss) and cash distributions		$ 0				$ 13,264,000				$ 0	$ 13,264,000
Ownership interest, percent		24.95%								24.95%			24.95%

Acquisition - Narrative (Detail

Acquisition - Narrative (Details) - USD ($) $ in Thousands	Mar. 06, 2015	Nov. 20, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Asset impairment charges			$ 520	$ 2,087	$ 355
ADA Analytics Israel, LLC
Business Acquisition [Line Items]
Cash paid	$ 2,360	$ 200
Cash paid to acquire business, VAT tax	400
Contingent consideration, liability	$ 500
Asset impairment charges				$ 1,900

Acquisition - Consideration and

Acquisition - Consideration and Allocation (Details) - ADA Analytics Israel, LLC - USD ($) $ in Thousands	Mar. 06, 2015	Nov. 20, 2014
Business Acquisition [Line Items]
Cash paid	$ 2,360	$ 200
Accrued liabilities	10
Contingent consideration	451
Total fair value of liabilities assumed	461
Total purchase consideration	2,821
Receivables	360
Property and equipment and other	82
Intangibles - in process research and development	2,379
Total	$ 2,821

Related Party Transactions - Na

Related Party Transactions - Narrative (Details) $ in Thousands, £ in Millions

Jun. 30, 2016USD ($)

Oct. 22, 2015USD ($)

Mar. 06, 2015USD ($)

Nov. 20, 2014USD ($)

Feb. 29, 2016USD ($)

Mar. 31, 2016USD ($)

Sep. 30, 2014USD ($)

Dec. 31, 2016USD ($)

Dec. 31, 2015USD ($)seatshares

Dec. 31, 2014USD ($)

Dec. 31, 2013USD ($)

Dec. 31, 2016GBP (£)

Nov. 30, 2016USD ($)

Jun. 15, 2016USD ($)

Jun. 15, 2016GBP (£)

Mar. 30, 2016USD ($)

Mar. 03, 2016

Nov. 30, 2014

Feb. 28, 2014

Feb. 10, 2014

Transactions with Third Party [Line Items]

Short-term note payable

$ 0

$ 12,676

Debt issuance costs, net

$ 100

Gain on contract termination

891

0

$ 0

Deferred revenue, related party

$ 2,000

2,000

Board Member

Transactions with Third Party [Line Items]

Compensation

$ 100

ADA Analytics Israel, LLC

Transactions with Third Party [Line Items]

Cash paid

$ 2,360

$ 200

ADA Analytics Israel, LLC | General and Administrative Expense

Transactions with Third Party [Line Items]

Expenses associated with related parties

200

$ 200

ADA Analytics Israel, LLC | Prepaid Expenses and Other Current Assets

Transactions with Third Party [Line Items]

Cash paid

$ 200

RCM6, LLC (RCM6) | Disposed of by Sale

Transactions with Third Party [Line Items]

Ownership percentage sold

24.95%

RCM6, LLC (RCM6)

Transactions with Third Party [Line Items]

Effective interest rate

20.00%

Stated interest rate

1.65%

Discount

7,600

Ownership percentage sold

24.95%

24.95%

24.95%

Highview Enterprises Limited

Transactions with Third Party [Line Items]

Ownership percentage sold

8.00%

Highview Enterprises Limited | Licensed technology

Transactions with Third Party [Line Items]

Long-term licensing agreement, period

10 years

Long-term licensing agreement, obligations

1,600

Long-term licensing agreement, termination fee

$ 200

£ 0.2

$ 200

£ 0.2

Gain on contract termination

200

Term Loan

Transactions with Third Party [Line Items]

Short-term note payable

$ 15,000

Term loan extension option term

3 months

Effective interest rate

10.50%

15.00%

Proceeds from debt, net of discount

$ 13,500

Debt discount and debt issuance costs

1,500

Restricted cash

$ 3,000

$ 3,500

Debt issuance costs, net

$ 600

Extinguishment of debt, amount

$ 9,900

Prepayment premium

4.00%

Tinuum Group

Transactions with Third Party [Line Items]

Proceeds from royalties received

$ 10,000

Advance deposit from related party

$ 0

3,000

Affiliated Entity

Transactions with Third Party [Line Items]

Extinguishment of debt, amount

$ 300

$ 300

Due to related parties

$ 1,100

Arch

Transactions with Third Party [Line Items]

Deferred revenue, related party

2,000

Fees related to related party agreement

$ 300

Number of seats on board | seat

1

Arch | Minimum

Transactions with Third Party [Line Items]

Common stock held (in shares) | shares

200,000

Related Party Transactions - Am

Related Party Transactions - Amounts Recorded to Related Party (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Royalties, related party	$ 2,203	$ 2,064	$ 669	$ 1,189	$ 2,876	$ 3,273	$ 2,299	$ 2,194	$ 6,125	$ 10,642	$ 6,410
Tinuum Group
Related Party Transaction [Line Items]
Receivable from related party	1,934				1,918				1,934	1,918
Revenues from related party									0	55	665
Royalties, related party									6,125	10,642	$ 6,410
RCM6, LLC (RCM6)
Related Party Transaction [Line Items]
Payable to related party	$ 0				$ 270				$ 0	$ 270

Related Party Transactions - Su

Related Party Transactions - Summary of Notes Payable with Related Parties (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Short-term note payable	$ 0	$ 12,676
Current portion of long-term borrowings	0	1,837
Total Short-term and current portion of long-term borrowings	0	14,513
Long-term borrowings	0	13,512
Total Borrowings	0	28,025
Franklin Mutual
Related Party Transaction [Line Items]
Short-term note payable	0	12,676
RCM6 note payable, net of discount
Related Party Transaction [Line Items]
Current portion of long-term borrowings	0	1,207
Long-term borrowings	0	13,023
DSI Business Owner note payable
Related Party Transaction [Line Items]
Current portion of long-term borrowings	0	630
Long-term borrowings	$ 0	$ 489

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Time deposits, $250,000 or more	$ 250	$ 250
Note receivable					$ 1,000
Interest rate					8.00%
Asset impairment charges		520	$ 2,087	$ 355
Property and equipment	735	735	2,040
Proceeds from sale of property and equipment		52	942	$ 26
Cost of Sales | Nonrecurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges		800
Other Nonoperating Income (Expense) [Member] | Highview Enterprises Limited | Cost method investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment charges	$ 1,800
Disposed of by Sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges		$ 500
Proceeds from sale of impaired assets			600
Property and equipment			100
Proceeds from sale of property and equipment			300
Gain on disposition of assets			200
Disposed of by Sale | General and Administrative Expense
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges			$ 300

Fair Value Measurements - Estim

Fair Value Measurements - Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 29, 2016	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Investment securities:
Investment securities, restricted, long-term			$ 0	$ 336
Notes Payable:
Short-term borrowings, net of discount and deferred loan costs, related party			0	12,676
Affiliated Entity
Notes Payable:
Extinguishment of debt, amount	$ 300	$ 300
Carrying Value
Investment securities:
Investment securities, restricted, long-term			0	336
Cost method investment			1,016	2,776
Notes Payable:
Short-term borrowings, net of discount and deferred loan costs, related party			0	12,676
Current portion of notes payable, related parties			0	1,837
Long-term portion of notes payable, related parties			0	13,512
Highview technology license payable			207	519
Highview technology license payable, long-term			0	1,038
Stock appreciation rights, liability-classified equity award			0	742
Fair Value
Investment securities:
Investment securities, restricted, long-term			0	336
Cost method investment			1,016	2,776
Notes Payable:
Short-term borrowings, net of discount and deferred loan costs, related party			0	12,676
Current portion of notes payable, related parties			0	1,457
Long-term portion of notes payable, related parties			0	13,273
Highview technology license payable			207	519
Highview technology license payable, long-term			0	1,038
Stock appreciation rights, liability-classified equity award			$ 0	$ 742

Fair Value Measurements - Finan

Fair Value Measurements - Financial Instruments Carried and Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, restricted, long-term	$ 0	$ 336
Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, restricted, long-term		336
Total assets at fair value		336
Stock appreciation rights, liability-classified equity award		742
Total liabilities at fair value		742
Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, restricted, long-term		0
Total assets at fair value		0
Stock appreciation rights, liability-classified equity award		0
Total liabilities at fair value		0
Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, restricted, long-term		336
Total assets at fair value		336
Stock appreciation rights, liability-classified equity award		742
Total liabilities at fair value		742
Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities, restricted, long-term		0
Total assets at fair value		0
Stock appreciation rights, liability-classified equity award		0
Total liabilities at fair value		$ 0

Supplemental Financial Inform67

Supplemental Financial Information - Prepaid expenses and other assets and Other assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other current assets:
Prepaid expenses	$ 1,169	$ 2,117
Inventory	16	189
Other	172	0
Other current assets	1,357	2,306
Other long-term assets:
Deposits	263	414
Intangibles	696	1,941
Other long-term assets	323	341
Total	$ 1,282	$ 2,696

Supplemental Financial Inform68

Supplemental Financial Information - Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other current liabilities:
Accrued consultant incentives	$ 0	$ 369
Accrued interest	618	1,042
Accrued losses on equipment contracts	183	759
Taxes payable	244	521
Deferred revenue	76	682
Warranty liabilities	287	1,197
Deferred rent	369	0
Asset retirement obligation	1,312	1,248
Other	928	1,577
Other current liabilities	4,017	7,395
Other long-term liabilities:
Deferred rent	38	767
Advance deposit, related party	0	2,981
Deferred revenue, related party	2,000	2,000
Other long-term liabilities	0	2,604
Total other long-term liabilities	$ 2,038	$ 8,352

Supplemental Financial Inform69

Supplemental Financial Information - Warranty Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Beginning balance	$ 1,197	$ 152
Warranties accrued, net	89	1,337
Warranty claims	(899)	(292)
Change in estimate related to previous warranties accrued	(100)	0
Ending balance	$ 287	$ 1,197

Supplemental Financial Inform70

Supplemental Financial Information - Asset Retirement Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, beginning of year	$ 1,248	$ 1,188
Accretion	64	60
Asset retirement obligations, end of year	$ 1,312	$ 1,248

Supplemental Financial Inform71

Supplemental Financial Information - Supplemental Income Statement - Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
453A interest	$ 2,490	$ 4,639	$ 3,371
Interest on RCM6 note payable, related party	263	2,468	2,245
Credit agreement interest	1,884	1,180	0
Other	429	115	109
Interest expense	$ 5,066	$ 8,402	$ 5,725

Supplemental Financial Inform72

Supplemental Financial Information Supplemental Financial Information - Supplemental Income Statement - Other (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Gain on sale of equity method investment	$ 2,078	$ 0	$ 0
Gain on settlement of note payable and licensed technology	1,019	0	0
Impairment of cost method investment	(1,760)	0	0
Gain on termination of sales-type lease	891	0	0
Other	235	494	26
Other nonoperating income (expense)	$ 2,463	$ 494	$ 26

Stockholders Equity (Details)

Stockholders Equity (Details)	Mar. 14, 2014	Dec. 31, 2016shares	Dec. 31, 2015shares
Stockholders' Equity Note [Abstract]
Preferred stock, shares outstanding (in shares)		0	0
Stock split, conversion ratio	2

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details)	12 Months Ended
	Dec. 31, 2016USD ($)employee$ / sharesshares	Dec. 31, 2015USD ($)employee$ / sharesshares	Dec. 31, 2014USD ($)employee$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees affected | employee	27	37	17
Net increase in share-based compensation	$ 400,000	$ 3,400,000	$ 1,000,000
Stock-based compensation	2,762,000	6,462,000	4,712,000
Stock-based compensation expense	2,868,000	7,204,000	4,712,000
Reclassification and settlement of equity awards	899,000		501,000
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	2,762,000	$ 6,462,000	4,712,000
Reclassification and settlement of equity awards	$ 899,000		$ 501,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Expected term (in years)	2 years 7 months 6 days	5 years	5 years
Contractual term	5 years
Expiration period	5 years
Weighted-average grant-date fair value	$ 500,000	$ 800,000	$ 600,000
Intrinsic value of options exercised	0	0	4,900,000
Shares issued as a result of options exercised	0	0	6,100,000
Stock-based compensation expense	$ 285,000	$ 658,000	$ 117,000
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees affected | employee	27	37	17
Aggregate weighted average grant-date fair value of share granted	$ 2,700,000	$ 1,900,000	$ 2,800,000
Fair value of shares vested	2,100,000	2,900,000	1,900,000
Stock-based compensation expense	$ 2,021,000	$ 2,909,000	$ 2,612,000
Exercise price (in usd per share) | $ / shares	$ 11.96	$ 17.51	$ 15.75
Restricted stock awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Restricted stock awards | Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares accelerated, number (in shares) | shares	42,852	95,088	55,106
Stock-based compensation	$ 300,000	$ 1,200,000	$ 1,000,000
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Expected term (in years)	5 years	5 years
Aggregate weighted average grant-date fair value of share granted	$ 0	$ 0
Stock-based compensation expense	$ 106,000	$ 742,000	$ 0
Exercise price (in usd per share) | $ / shares	$ 0	$ 0
Stock appreciation rights | Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 500,000
Exercise price (in usd per share) | $ / shares	$ 13.87
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		3 years	3 years
Service period	3 years
Net increase in share-based compensation	$ 100,000	$ 2,100,000	$ 200,000
Aggregate weighted average grant-date fair value of share granted	0	1,400,000	2,200,000
Stock-based compensation expense	$ 456,000	$ 2,895,000	$ 1,983,000
Exercise price (in usd per share) | $ / shares	$ 26.87	$ 30.52	$ 0
Other matters
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from share-based payment exercises	$ 0	$ 0	$ 200,000
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares) | shares	180,000
2005 Plan | Stock compensation plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee (in shares) | shares	2,000
Shares reserved for issuance (in shares) | shares	100,000
2005 Plan | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee (in shares) | shares	10,000
Shares reserved for issuance (in shares) | shares	80,000
Vesting period	3 years
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee (in shares) | shares	400,000
Shares authorized for issuance (in shares) | shares	3,600,000
Maximum number of common shares to be received by participant, percent	200.00%
Maximum reduction in number of common shares to be received by participants, percent	0.00%
Percent of award based on performance of total stockholder return	75.00%
2007 Plan | Non-management Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares per employee (in shares) | shares	50,000
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares) | shares	600,000
401 (k) Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance (in shares) | shares	600,000

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions for Stock Options (Details) - Stock options	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.30%	1.80%	1.60%
Dividend yield	0.00%	0.00%	0.00%
Volatility	78.80%	74.50%	80.40%
Expected term (in years)	2 years 7 months 6 days	5 years	5 years

Stock-Based Compensation - Fa76

Stock-Based Compensation - Fair Value Assumptions for SAR (Details) - Stock appreciation rights	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.80%
Dividend yield		0.00%
Volatility		74.50%
Expected term (in years)	5 years	5 years

Stock-Based Compensation - Fa77

Stock-Based Compensation - Fair Value Assumptions for PSU (Details) - Performance share units	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.00%	0.80%
Dividend yield	0.00%	0.00%
Volatility	64.30%	74.50%
Performance period (in years)	3 years	3 years

Stock-Based Compensation - Allo

Stock-Based Compensation - Allocation of Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 2,868	$ 7,204	$ 4,712
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	2,021	2,909	2,612
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	285	658	117
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	106	742	0
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 456	$ 2,895	$ 1,983

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Unrecognized Compensation Cost (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based compensation expense	$ 2,204
Expected Weighted-Average Period of Recognition (in years)	9 months 23 days
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, equity instruments other than options	$ 1,335
Expected Weighted-Average Period of Recognition (in years)	11 months 23 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, options	$ 732
Expected Weighted-Average Period of Recognition (in years)	6 months 11 days
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, equity instruments other than options	$ 137
Expected Weighted-Average Period of Recognition (in years)	7 months 17 days

Stock-Based Compensation - Su80

Stock-Based Compensation - Summary of Non-vested Restricted Stock Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Weighted Average Grant Date Fair Value
Total stock-based compensation expense	$ 2,868	$ 7,204	$ 4,712
Restricted stock awards
Shares
Non-vested shares, Beginning balance (in shares)	134,708	209,921	263,989
Granted (in shares)	363,758	127,943	112,643
Vested (in shares)	(175,956)	(165,796)	(118,364)
Forfeited (in shares)	(25,163)	(37,360)	(48,347)
Non-vested shares, Ending balance (in shares)	297,347	134,708	209,921
Weighted Average Grant Date Fair Value
Nonvested shares, Weighted Average Grant Date Fair Value, Beginning Balance (in usd per share)	$ 8.49	$ 13.59	$ 9.05
Non vested shares granted, Weighted Average Grant Date Fair Value (in usd per share)	7.46	14.97	24.74
Vested in period, Weighted Average Grant Date Fair Value (in usd per share)	11.96	17.51	15.75
Forfeited, Weighted Average Grant Date Fair Value (in usd per share)	15.58	19.30	9.49
Non-vested shares, Weighted Average Grant Date Fair Value, Ending Balance (in usd per share)	$ 8.03	$ 8.49	$ 13.59
Total stock-based compensation expense	$ 2,021	$ 2,909	$ 2,612
Restricted stock awards | Other
Weighted Average Grant Date Fair Value
Total stock-based compensation expense	$ 100

Stock-Based Compensation - Su81

Stock-Based Compensation - Summary of Option Activity (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Options Outstanding and Exercisable
Options outstanding, beginning of year (in shares)	106,250	74,200	317,576
Options granted (in shares)	546,196	56,250	30,000
Options exercised (in shares)	0	0	(260,126)
Options expired / forfeited (in shares)	(20,000)	(24,200)	(13,250)
Options outstanding, end of year (in shares)	632,446	106,250	74,200
Options vested and exercisable (in shares)	247,780	82,915	34,199
Weighted Average Exercise Price
Options outstanding, end of year (in usd per shares)	$ 15.22	$ 13.76	$ 5.07
Options granted (in usd per shares)	11.10	13.87	20.67
Options exercised (in usd per shares)	0	0	4.30
Options expired / forfeited (in usd per shares)	16.90	7.59	6.90
Options outstanding, end of year (in usd per shares)	11.61	15.22	13.76
Options vested and exercisable,Weighted Average Exercise Price (in usd per shares)	$ 13.30	$ 14.04	$ 8.44
Options outstanding, end of year, Aggregate Intrinsic Value	$ 183	$ 0	$ 670
Options outstanding, end of year, Weighted Average Remaining Contractual Term (in years)	4 years	3 years 9 months 18 days	3 years
Options vested and exercisable, Aggregate Intrinsic Value	$ 69	$ 0	$ 491
Options vested and exercisable, Weighted Average Remaining Contractual Term (in years)	3 years 4 months 24 days	3 years 10 months 24 days	1 year 7 months 6 days
2007 Equity Incentive Plan
Number of Options Outstanding and Exercisable
Options granted (in shares)	243,750

Stock-Based Compensation - Su82

Stock-Based Compensation - Summary of SARs (Details) - Stock appreciation rights - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Shares
Non-vested shares, Beginning balance (in shares)	243,750	0
Granted (in shares)	0	243,750
Vested (in shares)	0	0
Forfeited/Canceled (in shares)	(243,750)	0
Non-vested shares, Ending balance (in shares)	0	243,750
Weighted Average Grant Date Fair Value
Nonvested shares, Weighted Average Grant Date Fair Value, Beginning Balance (in usd per share)	$ 13.87	$ 0
Non vested shares granted, Weighted Average Grant Date Fair Value (in usd per share)	0	13.87
Vested in period, Weighted Average Grant Date Fair Value (in usd per share)	0	0
Forfeited, Weighted Average Grant Date Fair Value (in usd per share)	13.87	0
Non-vested shares, Weighted Average Grant Date Fair Value, Ending Balance (in usd per share)	$ 0	$ 13.87
Aggregate weighted average grant-date fair value of share granted	$ 0	$ 0
SARs outstanding, weighted average remaining contractual term		4 years 6 months
SARs vested and exercisable (in shares)	0	43,750
SARs vested and exercisable, weighted average exercise price (in usd per share)	$ 0	$ 13.87
SARs exercisable, intrinsic value	$ 0	$ 0

Stock-Based Compensation - Su83

Stock-Based Compensation - Summary of Non-vested PSUs (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Weighted Average Grant Date Fair Value
Stock-based compensation expense	$ 2,868	$ 7,204	$ 4,712
Performance share units
Shares
Non-vested shares, Beginning balance (in shares)	169,334	142,357	89,578
Granted (in shares)	0	69,218	57,547
Vested (in shares)	(119,818)	(13,763)	0
Forfeited/Canceled (in shares)	0	(28,478)	(4,768)
Non-vested shares, Ending balance (in shares)	49,516	169,334	142,357
Weighted Average Grant Date Fair Value
Nonvested shares, Weighted Average Grant Date Fair Value, Beginning Balance (in usd per share)	$ 26.38	$ 30.65	$ 26.04
Non vested shares granted, Weighted Average Grant Date Fair Value (in usd per share)	0	20.10	37.45
Vested in period, Weighted Average Grant Date Fair Value (in usd per share)	26.87	30.52	0
Forfeited, Weighted Average Grant Date Fair Value (in usd per share)	0	30.44	26.04
Non-vested shares, Weighted Average Grant Date Fair Value, Ending Balance (in usd per share)	$ 25.20	$ 26.38	$ 30.65
Stock-based compensation expense	$ 456	$ 2,895	$ 1,983
Performance share units | Other
Weighted Average Grant Date Fair Value
Stock-based compensation expense	$ 200

Stock-Based Compensation Stock-

Stock-Based Compensation Stock-Based Compensation - PSUs Settled (Details) - Performance share units	12 Months Ended
	Dec. 31, 2016shares	Dec. 31, 2015shares
2,013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Number of Issued Shares upon Vesting (in shares)	38,706	8,768
Shares Withheld to Settle Tax Withholding Obligations (in shares)	1,572	3,954
2013 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	0.63	1.75
Russell 3000 Multiple	0	2
2013 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	1	1.75
Russell 3000 Multiple	0	2
2,014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Number of Issued Shares upon Vesting (in shares)	11,487	2,506
Shares Withheld to Settle Tax Withholding Obligations (in shares)	0	1,145
2014 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	0.63	0.63
Russell 3000 Multiple	0	0
2014 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	0.63	0.75
Russell 3000 Multiple	0	0.75
2,015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Number of Issued Shares upon Vesting (in shares)	13,529
Shares Withheld to Settle Tax Withholding Obligations (in shares)	0
2015 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	0.50
Russell 3000 Multiple	0
2015 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
TSR Multiple Range	0.50
Russell 3000 Multiple	0

Commitments and Contingencies -

Commitments and Contingencies - Legal Proceedings (Details) $ in Millions	Dec. 31, 2016USD ($)
Denver Settlement | Monetary Damages
Loss Contingencies [Line Items]
Loss contingency accrual	$ 4
Derivative Settlement | Legal and Professional Fees
Loss Contingencies [Line Items]
Loss contingency accrual	$ 0.6

Commitments and Contingencies86

Commitments and Contingencies - SEC Inquiry (Details) $ in Millions	Dec. 31, 2016USD ($)
SEC Inquiry | Monetary Damages
Loss Contingencies [Line Items]
Loss contingency accrual	$ 0.5

Commitments and Contingencies87

Commitments and Contingencies - Settlement and Royalty Indemnity, Narrative (Details) - USD ($)	1 Months Ended		3 Months Ended	12 Months Ended
	Nov. 30, 2011	Aug. 31, 2011	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Loss Contingencies [Line Items]
Reduction to royalty award accrual			$ 4,000,000	$ 4,000,000
Settlement and royalty indemnification			5,656,000	5,656,000	$ 6,502,000
Settlement and royalty indemnification, long-term			$ 5,382,000	$ 5,382,000	$ 13,797,000
Norit Litigation
Loss Contingencies [Line Items]
Period of payment for equity award after each quarter		3 months
Ability to pay dividends, percent of market fair value	50.00%
Benchmark for earnings for increase in letters of credit	$ 20,000,000
Increase in letters of credit as collateral	5,000,000
Maximum amount of increase in letters of credit based on dividends or earnings	$ 7,500,000

Commitments and Contingencies88

Commitments and Contingencies - Settlement and Royalty Indemnity (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Settlement and Royalty Indemnification	$ 5,656	$ 6,502
Legal settlements	5,050	0
Legal settlements and accruals, current	10,706	6,502
Settlement and Royalty Indemnification, long-term	5,382	13,797
Legal settlements and accruals, long-term	$ 16,088	$ 20,299

Commitments and Contingencies89

Commitments and Contingencies - Tinuum Group and Consultant Obligation (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Legal and professional fees		$ 8,293	$ 16,604	$ 14,430
Tinuum Group
Related Party Transaction [Line Items]
Limited guarantees, percent		50.00%
Legal and professional fees			$ 300	$ 1,400
Payment for professional fees	$ 300

Commitments and Contingencies90

Commitments and Contingencies - Line of Credit (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Nov. 30, 2016	Sep. 30, 2013
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 15,000,000	$ 10,000,000
Line of credit facility, interest rate during period	5.00%
Origination fee		100,000
Deposit account balance requirement		6,000,000
Requirements for EBITDA		24,000,000
Remaining borrowing capacity	$ 13,200,000
After certain conditions are met
Debt Instrument [Line Items]
Deposit account balance requirement		$ 3,000,000
Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%

Commitments and Contingencies91

Commitments and Contingencies - Letters of Credit (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other Commitments [Line Items]
LOC Outstanding	$ 15,505	$ 12,034
Restricted cash	13,736	728
Restricted cash, long-term	0	10,980
Investment securities, restricted, long-term	0	336
Letter of Credit
Other Commitments [Line Items]
Utilization of LOC Availability	1,776	0
Long-term Debt, Fiscal Year Maturity
Expiration of Letters of Credit - Less than 1 year	10,855
Expiration of Letters of Credit - 1-3 years	4,650
Expiration of Letters of Credit - 4-5 years	0
Expiration of Letters of Credit - After 5 years	0
Contract performance - equipment systems
Other Commitments [Line Items]
LOC Outstanding	1,855	5,556
Restricted cash	86	728
Restricted cash, long-term	0	4,830
Investment securities, restricted, long-term	0	0
Contract performance - equipment systems | Letter of Credit
Other Commitments [Line Items]
Utilization of LOC Availability	1,776	0
Royalty award
Other Commitments [Line Items]
LOC Outstanding	7,150	6,150
Restricted cash	7,150	0
Restricted cash, long-term	0	6,150
Investment securities, restricted, long-term	0	0
Royalty award | Letter of Credit
Other Commitments [Line Items]
Utilization of LOC Availability	0	0
Other
Other Commitments [Line Items]
LOC Outstanding	6,500	328
Restricted cash	6,500	0
Restricted cash, long-term	0	0
Investment securities, restricted, long-term	0	336
Other | Letter of Credit
Other Commitments [Line Items]
Utilization of LOC Availability	$ 0	$ 0

Commitments and Contingencies92

Commitments and Contingencies - Purchase Obligations (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Equipment Systems, ACI
Loss Contingencies [Line Items]
Performance guarantees testing, cost incurred	$ 0.9

Commitments and Contingencies93

Commitments and Contingencies - Operating Lease Obligations (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)ft²lease	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Commitments and Contingencies Disclosure [Abstract]
Square feet under lease | ft²	52,869
Number of leases | lease	3
Termination fee	$ 300
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,017	290
2,018	268
2,019	174
2,020	55
Thereafter	0
Total	787
Rent expense	$ 847	$ 1,838	$ 1,531
Minimum
Lease And Rental Expense [Line Items]
Operating leases, term of contract	4 years
Maximum
Lease And Rental Expense [Line Items]
Operating leases, term of contract	7 years

Defined Contributions Savings94

Defined Contributions Savings Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
401(k) employer expense
Defined Benefit Plan Disclosure [Line Items]
Employer expense	$ 173	$ 439	$ 509

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (61,673)	$ 583	$ 99	$ 53	$ (131)	$ 44	$ 63	$ 44	$ (60,938)	$ 20	$ 296
Valuation allowance adjustments	(61,400)
Net deferred tax assets	61,396				0				61,396	0
Period increase (decrease)									(11,000)
Allowances against the net deferred tax assets	$ 75,910				$ 148,269				75,910	$ 148,269
Unrecognized tax benefits that would impact effective tax rate									$ (72,400)

Income Taxes - Income Tax Benef

Income Taxes - Income Tax Benefit (Expense) from Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current portion of income tax expense:
Federal									$ 0	$ 0	$ 0
State									458	20	296
Current portion of income tax expense									458	20	296
Deferred portion of income tax (benefit) expense:
Federal									(61,396)	0	0
State									0	0	0
Deferred portion of income tax (benefit) expense									(61,396)	0	0
Total income tax (benefit) expense	$ (61,673)	$ 583	$ 99	$ 53	$ (131)	$ 44	$ 63	$ 44	$ (60,938)	$ 20	$ 296
Effective tax rate									(166.00%)	0.00%	18.00%

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Expected Federal Income Taxes at Statutory Rates (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amount
Federal statutory rate									$ 12,859	$ (10,542)	$ 589
State income taxes, net of federal benefit									987	(781)	31
Disallowed compensation									0	0	721
Permanent differences									84	35	52
Tax credits									(2,419)	(38,998)	(25,607)
Valuation allowances									(72,359)	50,066	23,794
Changes in state effective rates									(125)	(243)	716
Stock-based compensation									36	487	0
Other									(1)	(4)	0
Total income tax (benefit) expense	$ (61,673)	$ 583	$ 99	$ 53	$ (131)	$ 44	$ 63	$ 44	$ (60,938)	$ 20	$ 296

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets And Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Settlement and Royalty Indemnification	$ 4,264	$ 7,807
Deferred revenues and loss contract provisions	268	2,899
Employee related liabilities	3,796	4,598
Intangible assets	1,518	1,733
Equity method investments	12,326	7,500
Net operating loss carryforward	13,341	23,193
Tax credits	99,903	97,484
Deposits on contracts	0	1,146
Other	2,109	2,118
Total deferred tax assets	137,525	148,478
Less: Deferred tax liabilities	(75,910)	(148,269)
Property and equipment and other	61,615	209
Less: Deferred tax liabilities
Property and equipment and other	(219)	(209)
Total deferred tax liabilities	(219)	(209)
Net deferred tax assets	$ 61,396	$ 0

Income Taxes - Net Operating Lo

Income Taxes - Net Operating Loss Carryforwards and Tax Credit Carryforwards (Details) $ in Thousands	Dec. 31, 2016USD ($)
Federal
Income Taxes [Line Items]
Net operating loss carryforwards	$ 31,699
Tax credit carryforwards	99,879
State
Income Taxes [Line Items]
Net operating loss carryforwards	$ 57,600

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance as of January 1	$ 0	$ 0	$ 0
Increases for tax positions of current year	54	0	0
Balance as of December 31	$ 54	$ 0	$ 0

Business Segment Information -

Business Segment Information - Segment Operating Results (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016USD ($)	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)segment	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment									2
Revenues:
Earnings from equity method investments	$ 15,518	$ 10,735	$ 13,754	$ 5,577	$ 3,788	$ (41)	$ 4,860	$ 314	$ 45,584	$ 8,921	$ 42,712
Equipment sales									46,949	60,099	12,044
Consulting services									648	1,752	4,488
Royalties, related party	2,203	2,064	669	1,189	2,876	3,273	2,299	2,194	6,125	10,642	6,410
Chemicals									3,025	888	391
Total reported revenues	3,604	15,710	8,951	22,357	13,202	12,885	14,895	21,757	50,622	62,739	16,923
Segment reporting operating income (loss)
Segment reporting operating income (loss)	$ (5,262)	$ (2,913)	$ (4,612)	$ (3,311)	$ (7,135)	$ (9,989)	$ (17,778)	$ (6,898)	(16,098)	(41,800)	(41,814)
Gain on sale of equity method investment									2,078	0	0
453A interest									2,490	4,639	3,371
Interest on RCM6 note payable, related party									263	2,468	2,245
Gain on contract termination									891	0	0
Operating Segments
Revenues:
Total reported revenues									102,331	82,302	66,045
Segment reporting operating income (loss)
Segment reporting operating income (loss)									58,598	4,548	28,746
Refined Coal | Operating Segments
Revenues:
Earnings from equity method investments									45,584	8,921	42,712
Consulting services									0	55	665
Royalties, related party									6,125	10,642	6,410
Total reported revenues									51,709	19,618	49,787
Segment reporting operating income (loss)
Segment reporting operating income (loss)									51,264	12,131	42,094
Refined Coal | Intersegment Eliminations
Revenues:
Earnings from equity method investments									(45,584)	(8,921)	(42,712)
Royalties, related party									(6,125)	(10,642)	(6,410)
Total reported revenues									(51,709)	(19,563)	(49,122)
Emissions Control | Operating Segments
Revenues:
Equipment sales									46,949	60,099	12,044
Consulting services									648	1,697	3,823
Chemicals									3,025	888	391
Total reported revenues									50,622	62,684	16,258
Segment reporting operating income (loss)
Segment reporting operating income (loss)									7,334	$ (7,583)	$ (13,348)
Gain on contract termination									$ 900

Business Segment Information102

Business Segment Information - Reconciliation of Reportable Segment Amounts (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total reported segment operating income	$ (5,262)	$ (2,913)	$ (4,612)	$ (3,311)	$ (7,135)	$ (9,989)	$ (17,778)	$ (6,898)	$ (16,098)	$ (41,800)	$ (41,814)
Corporate payroll and benefits									12,390	23,589	20,767
Corporate rent and occupancy									2,168	3,309	2,468
Corporate legal and professional fees									8,293	16,604	14,430
Corporate general and administrative									3,721	6,104	6,066
Corporate depreciation and amortization									979	2,019	1,865
Corporate interest (expense) income, net									268	24	74
Other income (expense), net									2,463	494	26
Income tax benefit (expense)	61,673	(583)	(99)	(53)	131	(44)	(63)	(44)	60,938	(20)	(296)
Net income (loss)	$ 75,830	$ 9,612	$ 7,860	$ 4,376	$ (2,908)	$ (8,654)	$ (12,447)	$ (6,132)	97,678	(30,141)	1,387
Operating Segments
Segment Reporting Information [Line Items]
Total reported segment operating income									58,598	4,548	28,746
Segment Reconciling Items
Segment Reporting Information [Line Items]
Corporate payroll and benefits									(9,415)	(14,842)	(12,621)
Corporate rent and occupancy									(1,187)	(707)	(694)
Corporate legal and professional fees									(8,230)	(15,199)	(9,514)
Corporate general and administrative									(3,811)	(3,640)	(3,980)
Corporate depreciation and amortization									(608)	(578)	(354)
Corporate interest (expense) income, net									(2,334)	24	74
Other income (expense), net									3,727	273	26
Income tax benefit (expense)									$ 60,938	$ (20)	$ (296)

Business Segment Information103

Business Segment Information - Segment Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 107,296	$ 60,775
Operating Segments | Refined Coal
Segment Reporting Information [Line Items]
Assets	6,310	19,507
Operating Segments | Emissions Control
Segment Reporting Information [Line Items]
Assets	24,551	31,467
All Other and Corporate
Segment Reporting Information [Line Items]
Assets	$ 76,435	$ 9,801

Major Customers - Sales to Unaf

Major Customers - Sales to Unaffiliated Customers (Details) - Sales	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Customer A
Revenue, Major Customer [Line Items]
Major customer percentage	21.00%	3.00%	0.00%
Customer B
Revenue, Major Customer [Line Items]
Major customer percentage	14.00%	16.00%	37.00%
Customer C
Revenue, Major Customer [Line Items]
Major customer percentage	1.00%	2.00%	24.00%
Customer D
Revenue, Major Customer [Line Items]
Major customer percentage	0.00%	11.00%	8.00%
Customer E
Revenue, Major Customer [Line Items]
Major customer percentage	0.00%	15.00%	0.00%

Quarterly Financial Results 105

Quarterly Financial Results (unaudited) - Summary (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 3,604	$ 15,710	$ 8,951	$ 22,357	$ 13,202	$ 12,885	$ 14,895	$ 21,757	$ 50,622	$ 62,739	$ 16,923
Cost of revenues, exclusive of operating expenses shown below	3,478	13,259	5,769	17,311	7,224	10,610	14,003	15,715
Other operating expenses	5,388	5,364	7,794	8,357	13,113	12,264	18,670	12,940
Operating loss	(5,262)	(2,913)	(4,612)	(3,311)	(7,135)	(9,989)	(17,778)	(6,898)	(16,098)	(41,800)	(41,814)
Earnings from equity method investments	15,518	10,735	13,754	5,577	3,788	(41)	4,860	314	45,584	8,921	42,712
Royalties, related party	2,203	2,064	669	1,189	2,876	3,273	2,299	2,194	6,125	10,642	6,410
Other income (expenses), net	1,698	309	(1,852)	974	(2,568)	(1,853)	(1,765)	(1,698)
Income (loss) before income tax expense	14,157	10,195	7,959	4,429	(3,039)	(8,610)	(12,384)	(6,088)	36,740	(30,121)	1,683
Income tax (benefit) expense	(61,673)	583	99	53	(131)	44	63	44	(60,938)	20	296
Net income (loss)	$ 75,830	$ 9,612	$ 7,860	$ 4,376	$ (2,908)	$ (8,654)	$ (12,447)	$ (6,132)	$ 97,678	$ (30,141)	$ 1,387
Net income (loss) per common share – basic (in dollars per share)	$ 3.45	$ 0.44	$ 0.36	$ 0.20	$ (0.13)	$ (0.40)	$ (0.57)	$ (0.28)	$ 4.40	$ (1.37)	$ 0.06
Net income (loss) per common share – diluted (in dollars per share)	$ 3.39	$ 0.43	$ 0.35	$ 0.20	$ (0.13)	$ (0.40)	$ (0.57)	$ (0.28)	$ 4.34	$ (1.37)	$ 0.06
Weighted-average number of common shares outstanding:
Basic (in shares)	21,693	21,740	21,875	21,849	21,676	21,687	21,715	21,696	21,931	21,773	21,554
Diluted (in shares)	22,061	22,098	22,187	22,177	21,676	21,687	21,715	21,696	22,234	21,773	22,079
Reduction to royalty award accrual	$ 4,000								$ 4,000
Valuation allowance adjustments	$ (61,400)