The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Intangible Assets (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Amortization related to intangible assets
Amortization expense	$ 25,812us-gaap_AmortizationOfIntangibleAssets	$ 13,338us-gaap_AmortizationOfIntangibleAssets	$ 50,754us-gaap_AmortizationOfIntangibleAssets	$ 24,636us-gaap_AmortizationOfIntangibleAssets	$ 72,754us-gaap_AmortizationOfIntangibleAssets	$ 44,086us-gaap_AmortizationOfIntangibleAssets	$ 6,615us-gaap_AmortizationOfIntangibleAssets
Future amortization expense of intangible assets
2015 (six months)	50,570		50,570
2016	97,432		97,432		83,449
2017	90,795		90,795		76,826
2018	86,818		86,818		72,857
2019	79,587		79,587		66,826
Thereafter	405,266		405,266		303,408
Total	810,468us-gaap_FiniteLivedIntangibleAssetsNet		810,468us-gaap_FiniteLivedIntangibleAssetsNet		692,336us-gaap_FiniteLivedIntangibleAssetsNet
Depreciation and amortization
Amortization related to intangible assets
Amortization expense	21,711	11,324	42,604	20,600	60,855	29,657	4,538
Cost of sales
Amortization related to intangible assets
Amortization expense	1,984	949	4,121	1,574	6,172	5,285	800
Interest expense
Amortization related to intangible assets
Amortization expense	$ 2,117	$ 1,065	$ 4,029	$ 2,462	$ 5,727	$ 3,375	$ 1,277