CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net (loss) income	$ (79,444)	$ 195,359
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	225,957	131,484
Deferred income taxes	(17,820)	(35,999)
Share-based compensation expense related to equity incentive plans	83,969	37,138
Excess tax benefit from share-based compensation	0	(407)
Amortization of debt discount on convertible debentures	24,413	23,746
Amortization of debt issuance costs	2,118	1,920
Losses on equity method investments	112	233
Gains on sale of assets	(75)	(860)
Losses on write-down of fixed assets	317	0
Impairment of intangible assets	1,984	530
Realized losses (gains) on available-for-sale investment	89	(13,959)
Realized gains on equity method investment	(468)	(2,225)
Amortization of premium on available-for-sale investments	0	4,732
Special charges	0	511
Changes in operating assets and liabilities, excluding impact of acquisitions:
(Increase) decrease in accounts receivable	(25,432)	5,170
Decrease (increase) in inventories	215,950	(4,597)
Increase in deferred income on shipments to distributors	39,764	13,492
Decrease in accounts payable and accrued liabilities	(22,017)	(31,443)
Change in other assets and liabilities	(13,641)	6,589
Operating cash flows related to discontinued operations	10,314	0
Net cash provided by operating activities	446,090	331,414
Cash flows from investing activities:
Purchases of available-for-sale investments	(25)	(1,112,089)
Sales and maturities of available-for-sale investments	470,565	795,771
Sale of equity method investment	468	2,667
Acquisition of Atmel, net of cash acquired	(2,747,516)	0
Acquisition of Micrel, net of cash acquired	0	(343,928)
Purchase of additional controlling interest in ISSC	0	(18,051)
Investments in other assets	(3,232)	(2,981)
Proceeds from sale of assets	66	14,296
Capital expenditures	(36,646)	(63,554)
Net cash used in investing activities	(2,316,320)	(727,869)
Cash flows from financing activities:
Repayments of revolving loan under credit facility	(951,500)	(190,000)
Proceeds from borrowings on revolving loan under credit facility	1,385,000	1,024,500
Deferred financing costs	0	(406)
Payment of cash dividends	(154,877)	(145,016)
Repurchase of common stock	0	(363,829)
Proceeds from sale of common stock	25,452	13,520
Tax payments related to shares withheld for vested restricted stock units	(35,843)	(11,124)
Capital lease payments	(391)	(334)
Excess tax benefit from share-based compensation	0	407
Net cash provided by financing activities	267,841	327,718
Effect of foreign exchange rate changes on cash and cash equivalents	(374)	0
Net decrease in cash and cash equivalents	(1,602,763)	(68,737)
Cash and cash equivalents at beginning of period	2,092,751	607,815
Cash and cash equivalents at end of period	$ 489,988	$ 539,078