CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Earnings (Deficit)
Balance at Dec. 31, 2018	$ 615,568	$ 439	$ 642,590	$ (11,893)	$ (15,568)
Balance (in shares) at Dec. 31, 2018		43,917,378
Net income	16,148				16,148
Issuance of common stock for debt conversion	2	$ 0	2
Issuance of common stock for debt conversion (in shares)		29
Exercise of stock options and vesting of stock units	566	$ 3	563
Exercise of stock options and vesting of stock units (in shares)		245,263
Issuance of common stock pursuant to the acquisition of C Technologies, Inc.	53,938	$ 8	53,930
Issuance of common stock pursuant to the acquisition of C Technologies, Inc., (in shares)		779,221
Proceeds from issuance of common stock, net of issuance cost of $0.5 million	189,623	$ 31	189,592
Proceeds from issuance of common stock, net of issuance cost of $0.5 million (in shares)		3,144,531
Stock-based compensation expense	6,283		6,283
Translation adjustment at Dec. 31, 2018	(3,160)			(3,160)
Balance at Jun. 30, 2019	878,968	$ 481	892,960	(15,053)	580
Balance (in shares) at Jun. 30, 2019		48,086,422
Balance at Mar. 31, 2019	625,025	$ 441	645,883	(13,784)	(7,515)
Balance (in shares) at Mar. 31, 2019		44,073,998
Net income	8,095				8,095
Issuance of common stock for debt conversion	2	$ 0	2
Issuance of common stock for debt conversion (in shares)		29
Exercise of stock options and vesting of stock units	523	$ 1	522
Exercise of stock options and vesting of stock units (in shares)		88,643
Issuance of common stock pursuant to the acquisition of C Technologies, Inc.	53,938	$ 8	53,930
Issuance of common stock pursuant to the acquisition of C Technologies, Inc., (in shares)		779,221
Proceeds from issuance of common stock, net of issuance cost of $0.5 million	189,623	$ 31	189,592
Proceeds from issuance of common stock, net of issuance cost of $0.5 million (in shares)		3,144,531
Stock-based compensation expense	3,031		3,031
Translation adjustment at Mar. 31, 2019	(1,269)			(1,269)
Balance at Jun. 30, 2019	878,968	$ 481	892,960	(15,053)	580
Balance (in shares) at Jun. 30, 2019		48,086,422
Balance at Dec. 31, 2019	1,059,768	$ 521	1,068,431	(15,027)	5,843
Balance (in shares) at Dec. 31, 2019		52,078,258
Net income	25,676				25,676
Exercise of stock options and vesting of stock units	5,402	$ 4	5,398
Exercise of stock options and vesting of stock units (in shares)		416,626
Stock-based compensation expense	8,267		8,267
Translation adjustment at Dec. 31, 2019	914			914
Balance at Jun. 30, 2020	1,100,027	$ 525	1,082,096	(14,113)	31,519
Balance (in shares) at Jun. 30, 2020		52,494,884
Balance at Mar. 31, 2020	1,069,758	$ 523	1,074,183	(20,606)	15,658
Balance (in shares) at Mar. 31, 2020		52,278,083
Net income	15,861				15,861
Exercise of stock options and vesting of stock units	3,813	$ 2	3,811
Exercise of stock options and vesting of stock units (in shares)		216,801
Stock-based compensation expense	4,102		4,102
Translation adjustment at Mar. 31, 2020	6,493			6,493
Balance at Jun. 30, 2020	$ 1,100,027	$ 525	$ 1,082,096	$ (14,113)	$ 31,519
Balance (in shares) at Jun. 30, 2020		52,494,884