The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Includes amortization of operating leases' right-of-use assets due to adoption of ASC 842 effective 1/1/19.

No definition available.

Restatement and Revision of Quarterly Condensed Consolidated Financial Statements - Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended	9 Months Ended			12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 16, 2013
Cash flows from operating activities:
Net income (loss)	$ (12,055)	$ (12,737)	$ (9,140)	$ (6,539)	$ (6,876)	$ (15,532)	$ (36,980)	$ (26,576)	$ (15,679)	$ (28,416)	$ (79,088)	$ (155,939)	$ (40,471)	$ (85,964)	$ (157,957)
Adjustments to reconcile net loss to net cash provided by operating activities:
Stock-based compensation				6,072					12,779	19,613	21,657	15,591	25,778	26,476	21,736
Depreciation expense and amortization of operating leases' right of use assets				7,711					15,447	21,675	16,226	8,107	29,773	23,644	10,745
Amortization of intangible assets				4,692					9,276	13,848	13,096	24,352	18,413	17,058	29,341
Non-cash interest expense and amortization of convertible debt issuance costs				1,773					3,571	5,394	5,104	7,587	7,243	6,854	9,243
Deferred income taxes				327					53	569	(2,118)	78,660	624	(1,816)	79,954
Non-cash restructuring				0					0	0	0	670	0	0	670
Loss on equity investment				212					318	521	424	0	747	696	67
Gain from sale of marketable equity security				0					0	0	0	(291)	0	0	(291)
Impairment (recovery) of assets held for sale		0	0	0		(1,853)			0	0	15,137	0
Gain from sale of assets held for sale				0					0	0	0	(1,266)	0	0	(1,266)
(Gain) loss from disposal of property, plant and equipment				0					2	(83)	141	518	(77)	157	395
Change in fair value of earn-out liability		0	0	(1,800)		0			(1,800)	(1,800)	0	0	(1,800)	0	0
Change in operating assets and liabilities, net of effects of acquisitions and divestiture:
Accounts receivable				(325)					8,841	11,014	10,423	(16,862)	16,136	4,994	(24,933)
Unbilled receivables				39,465					79,842	122,498	111,453	118,872	156,202	147,868	145,164
Prepaid expenses and other assets				1,855					1,726	2,114	4,544	(4,623)	2,057	4,076	(4,978)
Inventories				238					(1,468)	(4,132)	(3,121)	(1,271)	(4,380)	(3,353)	(1,856)
Accounts payable				416					1,709	1,063	4,798	153	(2,176)	2,934	(2,268)
Accrued salaries and benefits and other liabilities				(7,966)					(2,030)	(5,067)	(2,179)	(6,823)	3,353	6,176	(3,221)
Income taxes payable				(4,069)					(8,643)	(13,317)	(10,824)	(9,618)	(17,852)	(15,925)	(14,550)
Deferred revenue				(1,826)					(1,106)	3,003	(5,618)	(6,647)	(1,486)	(3,497)	228
Operating lease liabilities				(2,978)					(3,565)	(5,105)	(6,931)	0	(6,625)	(9,282)	0
Net cash provided by operating activities				37,258					99,273	143,392	93,124	51,170	185,459	128,535	86,223
Cash flows from investing activities:
Purchases of property, plant and equipment				(1,950)					(12,780)	(20,799)	(4,161)	(7,849)	(29,728)	(6,472)	(10,762)
Acquisition of intangible assets													0	0	350
Purchases of marketable securities				(169,866)					(487,521)	(655,063)	(463,850)	(192,824)	(898,957)	(657,433)	(282,117)
Maturities of marketable securities				215,164					407,556	527,971	377,852	181,704	817,834	507,385	223,079
Proceeds from sale of marketable securities				0					2,496	2,948	2,000	0	21,588	6,758	0
Proceeds from divestiture, net of cash disposed													0	76,039	0
Proceeds from sale of assets held for sale				0					0	0	0	4,648	0	0	4,648
Proceeds from sale of property and property, plant and equipment				0					0	0	29	10	0	29	10
Settlement of working capital adjustment from disposal of business				(1,131)					(1,131)	(1,131)	0	0	(1,131)	0	0
Proceeds from sale of equity security				0					0	0	0	1,350	0	0	1,350
Investment in privately-held companies				0					0	0	(1,000)	0	0	(1,000)	(3,000)
Acquisition of businesses, net of cash acquired				0					0	0	(21,779)	0	0	(66,780)	0
Net cash used in investing activities				42,217					(91,380)	(146,074)	(110,909)	(12,961)	(90,394)	(141,474)	(67,142)
Cash flows from financing activities:
Repayment of senior convertible notes				0					0	0	0	(81,207)	0	0	(81,207)
Proceeds received from issuance of common stock under employee stock plans				4,005					7,880	8,083	11,748	9,266	11,487	15,104	11,402
Payments under Installment				(2,551)					(6,600)	(9,152)	(4,330)	0	(13,201)	(8,379)	0
Principal payments against financing lease obligation				0					0	0	0	(786)	0	0	(1,080)
Repurchase and retirement of common stock, including prepayment under accelerated share repurchase program				0					0	0	0	(50,031)	(50,069)	0	(50,033)
Payments Related to Tax Withholding for Share-based Compensation				(7,218)					(7,663)	(8,785)	(5,665)	(5,964)	(9,403)	(7,023)	(6,766)
Net cash used in financing activities				(5,764)					(6,383)	(9,854)	1,753	(128,722)	(61,186)	(298)	(127,684)
Effect of exchange rate changes on cash and cash equivalents				(452)					(419)	(157)	(497)	(797)	106	(497)	(989)
Less: net decrease in cash classified within assets held for sale				0					0	0	(7,545)	0
Net increase (decrease) in cash, cash equivalents and restricted cash				73,259					1,091	(12,693)	(24,074)	(91,310)	33,985	(13,734)	(109,592)
Cash, cash equivalents and restricted cash at beginning of year	89,825	103,609	175,777	102,518	92,178			$ 116,252	102,518	102,518	116,252	225,844	102,518	116,252	225,844
Cash, cash equivalents and restricted cash at end of year	$ 136,503	$ 89,825	$ 103,609	$ 175,777	$ 102,518	$ 92,178			$ 103,609	$ 89,825	$ 92,178	$ 134,534	$ 136,503	$ 102,518	$ 116,252
1.125% convertible notes \| Convertible senior notes
Error corrections and prior period adjustments restatement
Stated Interest rate (as a percent)															1.125%	1.125%