Restatement of Consolidated Financial Statements - Schedule of Restatement Adjustments and Impact on Previously Reported Consolidated Statement of Operations (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales	$ 175,510	$ 170,812	$ 193,533	$ 194,322	$ 209,417	$ 220,881	$ 200,989	$ 176,049	$ 734,177	$ 807,336	$ 743,130
Cost of sales									579,109	564,089	543,596
Gross profit	17,179	34,413	45,241	58,235	63,186	74,649	59,900	45,512	155,068	243,247	199,534
Selling, general and administrative expenses									85,767	82,677	70,223
Research and development expenses									87,862	76,255	76,589
Restructuring and impairment charges									8,207		3,599
Special expense for IPO incentive											12,146
Operating income	(33,179)	(10,220)	2,665	13,966	21,913	32,492	20,345	9,565	(26,768)	84,315	36,977
Other income (expenses)
Interest expense, net									(20,360)	(22,600)	(24,984)
Foreign currency gain (loss), net									16,837	57,280	(11,348)
Loss on early extinguishment of senior notes									(32,812)		(5,459)
Others									2,870	3,890	1,628
Net other income (expense)									(33,465)	38,570	(40,163)
Income (loss) before income taxes									(60,233)	122,885	(3,186)
Income tax expenses (benefits)									3,970	12,847	8,115
Net income (loss)	(22,197)	251	(24,668)	(17,589)	47,009	47,210	2,458	13,361	(64,203)	110,038	(11,301)
Earnings (loss) per common share-
Basic	$ (0.64)	$ 0.01	$ (0.70)	$ (0.49)	$ 1.31	$ 1.30	$ 0.07	$ 0.36	$ (1.82)	$ 3.01	$ (0.29)
Diluted	$ (0.64)	$ 0.01	$ (0.70)	$ (0.49)	$ 1.27	$ 1.27	$ 0.07	$ 0.35	$ (1.82)	$ 2.93	$ (0.29)
Weighted average number of shares-
Basic	34,480,849	35,443,820	35,474,001	35,539,413	35,845,367	36,199,655	36,713,569	37,524,127	35,232,194	36,567,684	38,775,642
Diluted	34,480,849	37,484,601	35,474,001	35,539,413	37,050,284	37,290,612	37,517,712	38,282,932	35,232,194	37,533,391	38,775,642
As Previously Reported [Member]
Net sales		217,824	215,289	205,298	218,084	221,872	202,634	177,002		819,592	772,831
Cost of sales										556,091	538,515
Gross profit		71,888	71,048	65,743	74,288	76,440	62,858	49,915		263,501	234,316
Selling, general and administrative expenses										78,971	68,367
Research and development expenses										78,723	76,767
Restructuring and impairment charges											4,096
Special expense for IPO incentive											12,146
Operating income		30,625	30,208	22,924	35,347	35,582	23,003	11,875		105,807	72,940
Other income (expenses)
Interest expense, net										(22,600)	(24,984)
Foreign currency gain (loss), net										55,961	(11,633)
Loss on early extinguishment of senior notes											(5,459)
Others										2,119	(1,052)
Net other income (expense)										35,480	(43,128)
Income (loss) before income taxes										141,287	29,812
Income tax expenses (benefits)										(52,014)	8,019
Net income (loss)		46,671	4,436	(7,405)	125,286	48,412	4,340	15,263		193,301	21,793
Earnings (loss) per common share-
Basic		$ 1.32	$ 0.13	$ (0.21)	$ 3.50	$ 1.34	$ 0.12	$ 0.41		$ 5.29	$ 0.56
Diluted		$ 1.24	$ 0.12	$ (0.21)	$ 3.38	$ 1.30	$ 0.12	$ 0.40		$ 5.16	$ 0.55
Weighted average number of shares-
Basic		35,443,820	35,474,001	35,539,413	35,845,367	36,199,655	36,713,569	37,524,127		36,567,684	38,775,642
Diluted		37,493,550	37,125,005	35,539,413	37,074,657	37,324,787	37,566,699	38,298,336		37,496,965	39,774,898
Adjustments [Member]
Net sales		(47,012)	(21,756)	(10,976)	(8,667)	(991)	(1,645)	(953)		(12,256)	(29,701)
Cost of sales										7,998	5,081
Gross profit		(37,475)	(25,807)	(7,508)	(11,102)	(1,791)	(2,958)	(4,403)		(20,254)	(34,782)
Selling, general and administrative expenses										3,706	1,856
Research and development expenses										(2,468)	(178)
Restructuring and impairment charges											(497)
Operating income		(40,845)	(27,543)	(8,958)	(13,434)	(3,090)	(2,658)	(2,310)		(21,492)	(35,963)
Other income (expenses)
Foreign currency gain (loss), net										1,319	285
Others										1,771	2,680
Net other income (expense)										3,090	2,965
Income (loss) before income taxes										(18,402)	(32,998)
Income tax expenses (benefits)										64,861	96
Net income (loss)		(46,420)	(29,104)	(10,184)	(78,277)	(1,202)	(1,882)	(1,902)		(83,263)	(33,094)
Earnings (loss) per common share-
Basic		$ (1.31)	$ (0.83)	$ (0.28)	$ (2.19)	$ (0.04)	$ (0.05)	$ (0.05)
Diluted		$ (1.23)	$ (0.82)	$ (0.28)	$ (2.11)	$ (0.03)	$ (0.05)	$ (0.05)
Adjustments [Member] | Revenue Recognition [Member]
Net sales										(11,400)	(27,539)
Cost of sales										(1,301)	(10,104)
Gross profit										(10,099)	(17,435)
Selling, general and administrative expenses										(530)	(378)
Operating income										(9,569)	(17,057)
Other income (expenses)
Foreign currency gain (loss), net										1,281	121
Others										(449)	518
Net other income (expense)										832	639
Income (loss) before income taxes										(8,737)	(16,418)
Net income (loss)		(15,764)	(9,350)	(2,534)	(10,423)	3,502	(4,730)	2,914		(8,737)	(16,418)
Adjustments [Member] | Inventory Reserves [Member]
Cost of sales										7,810	10,075
Gross profit										(7,810)	(10,075)
Operating income										(7,810)	(10,075)
Other income (expenses)
Income (loss) before income taxes										(7,810)	(10,075)
Net income (loss)		(17,825)	(6,336)	(3,860)		(2,665)	2,352	(4,479)		(7,810)	(10,075)
Adjustments [Member] | Understated Employee Benefits [Member]
Cost of sales										833	1,740
Gross profit										(833)	(1,740)
Selling, general and administrative expenses										121	323
Research and development expenses										137	409
Operating income										(1,091)	(2,472)
Other income (expenses)
Income (loss) before income taxes										(1,091)	(2,472)
Net income (loss)						(3,378)				(1,091)	(2,472)
Adjustments [Member] | Settlement Obligations [Member]
Net sales										1,364
Cost of sales										485	2,116
Gross profit										879	(2,116)
Operating income										879	(2,116)
Other income (expenses)
Income (loss) before income taxes										879	(2,116)
Net income (loss)		1,412	(11,561)							879	(2,116)
Adjustments [Member] | Tax Matters [Member]
Selling, general and administrative expenses										773	1,223
Operating income										(773)	(1,223)
Other income (expenses)
Foreign currency gain (loss), net										(3)
Net other income (expense)										(3)
Income (loss) before income taxes										(776)	(1,223)
Income tax expenses (benefits)										64,861	96
Net income (loss)		(11,139)	(1,395)	(1,119)	(66,236)					(65,637)	(1,319)
Adjustments [Member] | Account Classification [Member]
Net sales										(2,220)	(2,162)
Cost of sales										2,651	707
Gross profit										(4,871)	(2,869)
Selling, general and administrative expenses											497
Research and development expenses										(2,651)	(707)
Restructuring and impairment charges											(497)
Operating income										(2,220)	(2,162)
Other income (expenses)
Others										2,220	2,162
Net other income (expense)										2,220	2,162
Adjustments [Member] | Cost Center Allocation [Member]
Cost of sales										(3,231)
Gross profit										3,231
Selling, general and administrative expenses										3,286
Research and development expenses										(55)
Adjustments [Member] | Other Adjustments [Member]
Cost of sales										751	547
Gross profit										(751)	(547)
Selling, general and administrative expenses										56	191
Research and development expenses										101	120
Operating income										(908)	(858)
Other income (expenses)
Foreign currency gain (loss), net										41	164
Net other income (expense)										41	164
Income (loss) before income taxes										(867)	(694)
Net income (loss)		$ (658)	$ (462)	$ (184)	$ (1,618)	$ 1,339	$ 496	$ (337)		$ (867)	$ (694)