Income taxes (Tables)

12 Months Ended

Mar. 31, 2017

Components of income tax expense (benefit)

The income tax provision consists of the following (amounts in thousands):



	Year Ended March 31,
	2017			2016			2015
Pretax Income:
U.S.	$	(279,304	)	$	(75,515	)	$	(944	)
Foreign	369,091			356,808			346,851
	$	89,787		$	281,293		$	345,907
Current expense (benefit):
U.S. Federal	$	21,287		$	(3,966	)	$	(3,185	)
State	1,004			(188		)	(24		)
Foreign	23,792			21,947			16,602
Total current	$	46,083		$	17,793		$	13,393
Deferred expense (benefit):
U.S. Federal	$	(114,743	)	$	(42,207	)	$	(22,641	)
State	(5,409		)	(1,990		)	(1,562		)
Foreign	(6,736		)	(16,228		)	(8,608		)
Total deferred	(126,888		)	(60,425		)	(32,811		)
Total	$	(80,805	)	$	(42,632	)	$	(19,418	)

Reconciliation of expected federal income tax expense to actual

The sources and tax effects of the differences in the total income tax provision are as follows (amounts in thousands):



	Year Ended March 31,
	2017			2016			2015
Computed expected income tax provision	$	31,425		$	98,453		$	121,067
State income taxes, net of federal benefits	(4,609		)	(1,246		)	(20		)
Research and development tax credits - current year	(12,852		)	(13,542		)	(9,703		)
Research and development tax credits - prior years	—			(2,511		)	(1,789		)
Foreign income taxed at lower than the federal rate	(105,069		)	(114,497		)	(106,939		)
Increases related to current and prior year tax positions	53,695			14,462			19,769
Decreases related to prior year tax positions ⁽¹⁾	(36,297		)	(12,103		)	(33,100		)
Withholding taxes	5,643			5,970			5,218
Change in valuation allowance	1,814			(2,482		)	(14,286		)
Intercompany prepaid tax asset amortization	7,931			(15,493		)	(1,089		)
Share-based compensation	(24,998		)	—			—
Other	2,512			357			1,454
Total	$	(80,805	)	$	(42,632	)	$	(19,418	)

⁽¹⁾ The release of prior year tax positions during fiscal 2017 increased each of the basic and diluted net income per common share by $0.17 and $0.15, respectively. The release of prior year tax positions during fiscal 2016 increased the basic and diluted net income per common share by $0.06. The release of prior year tax positions during fiscal 2015 increased each of the basic and diluted net income per common share by $0.16 and $0.15, respectively.

Schedule of deferred tax assets and liabilities

The tax effects of temporary differences that give rise to significant portions of the Company's deferred tax assets and deferred tax liabilities are as follows (amounts in thousands):



	March 31,
	2017			2016
Deferred tax assets:
Deferred income on shipments to distributors	$	55,674		$	34,830
Inventory valuation	14,608			12,082
Net operating loss carryforward	91,606			63,209
Capital loss carryforward	12,927			5,707
Share-based compensation	42,547			31,410
Income tax credits	243,049			100,294
Property, plant and equipment	59,700			16,262
Accrued expenses and other	110,347			37,292
Gross deferred tax assets	630,458			301,086
Valuation allowances	(210,120		)	(161,834		)
Deferred tax assets, net of valuation allowances	420,338			139,252
Deferred tax liabilities:
Convertible debt	(606,674		)	(496,626		)
Intangible assets	(147,543		)	(20,597		)
Other	(6,296		)	(6,416		)
Deferred tax liabilities	(760,513		)	(523,639		)
Net deferred tax liability	$	(340,175	)	$	(384,387	)

Reported as:
Non-current deferred tax assets	$	68,870		$	14,831
Non-current deferred tax liability	(409,045		)	(399,218		)
Net deferred tax liability	$	(340,175	)	$	(384,387	)

Rollforward of unrecognized tax benefits

The following table summarizes the activity related to the Company's gross unrecognized tax benefits from April 1, 2014 to March 31, 2017 (amounts in thousands):



	Year Ended March 31,
	2017			2016			2015
Beginning balance	$	220,669		$	170,654		$	149,878
Increases related to acquisitions	193,297			46,245			8,381
Decreases related to settlements with tax authorities	(11,729		)	(7,954		)	(20,197		)
Decreases related to statute of limitation expirations	(7,556		)	(4,591		)	(9,031		)
Increases related to current year tax positions	26,332			16,315			23,179
Decreases/Increases related to prior year tax positions	(22,536		)	—			18,444
Ending balance	$	398,477		$	220,669		$	170,654