Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating Activities
Net income	$ 156,523	$ 108,703
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	63,813	58,933
Amortization of acquired contract liabilities	(13,555)	(13,510)
Accretion of debt discount	268	4,272
Other amortization included in interest expense	1,811	7,948
Provision for doubtful accounts receivable	1,605	601
Provision for deferred income taxes	91,071	59,665
Employee stock-based compensation	3,162	2,397
Changes in assets and liabilities, excluding the effects of acquisitions and dispositions of businesses:
Trade and other receivables	41,642	(10,784)
Rotable assets	(1,176)	(5,874)
Inventories	(73,489)	(36,654)
Prepaid expenses and other current assets	(4,982)	(6,422)
Accounts payable, accrued expenses and other current liabilities	(60,600)	(24,521)
Accrued pension and other postretirement benefits	(73,391)	(85,766)
Changes in discontinued operations	0	241
Other	(213)	(1,881)
Net cash provided by operating activities	132,915	61,110
Investing Activities
Capital expenditures	(61,193)	(34,149)
Reimbursement Revenue	2,028	229
Proceeds from sale of assets	460	7,450
Acquisitions, net of cash acquired	0	19,205
Net cash used in investing activities	(58,705)	(7,265)
Financing Activities
Net increase in revolving credit facility	(81,709)	306,608
Proceeds from issuance of long-term debt	71,099	59,800
Repayment of debt and capital lease obligations	(55,853)	(417,701)
Payment of deferred financing costs	(2,244)	(3,903)
Dividends paid	(3,997)	(2,943)
Proceeds on government grant	1,000	0
Repurchase of restricted shares for minimum tax obligation	(1,840)	(608)
Proceeds from exercise of stock options	270	674
Net cash used in financing activities	(73,274)	(58,073)
Effect of exchange rate changes on cash	53	(350)
Net change in cash	989	(4,578)
Cash at beginning of period	29,662	39,328
Cash at end of period	$ 30,651	$ 34,750