Financing Arrangements (Tables)

6 Months Ended

Nov. 30, 2011

Financing Arrangements

Summary of recourse and non-recourse debt

	November 30,			May 31,
	2011			2011
Recourse debt:
Revolving credit facility expiring April 12, 2016 with interest payable monthly (see Note 8)	$	150,000		$	100,000
Revolving credit facility (secured by aircraft and related engines and components) due May 1, 2015 with floating interest rate, payable monthly	63,296			54,940
Note payable due July 19, 2012 with interest at 7.22%, payable monthly	9,421			2,217
Mortgage loan (secured by Wood Dale, Illinois facility) due August 1, 2015 with interest at 5.01%	11,000			11,000
Convertible notes payable due March 1, 2014 with interest at 1.625% payable semi-annually on March 1 and September 1	75,237			73,418
Convertible notes payable due March 1, 2016 with interest at 2.25% payable semi-annually on March 1 and September 1	52,485			51,309
Convertible notes payable due February 1, 2026 with interest at 1.75% payable semi-annually on February 1 and August 1	110,927			107,420
Industrial revenue bond (secured by trust indenture on property, plant and equipment) due August 1, 2018 with floating interest rate, payable monthly	25,000			25,000
Total recourse debt	497,366			425,304
Current maturities of recourse debt	(70,586		)	(111,323		)
Long-term recourse debt	$	426,780		$	313,981
Non-recourse debt:
Non-recourse note payable due December 8, 2011 with interest at 13.0%	$	6,545		$	—
Non-recourse note payable due July 19, 2012 with interest at 7.22%	—			8,201
Non-recourse note payable due April 3, 2015 with interest at 8.38%	—			3,654
Total non-recourse debt	6,545			11,855
Current maturities of non-recourse debt	(6,545		)	(823		)
Long-term non-recourse debt	$	—		$	11,032

Schedule of the long-term debt and equity component (recorded in capital surplus, net of income tax benefit) of convertible notes

	November 30,			May 31,
		2011			2011
Long-term debt:
Principal amount		$	268,380		$	268,380
Unamortized discount		(29,731		)	(36,233		)
Net carrying amount		$	238,649		$	232,147
Equity component, net of tax		$	74,966		$	74,966

Schedule of interest expense associated with the convertible notes

	Three Months Ended				Six Months Ended
	November 30,				November 30,
	2011		2010		2011		2010
Coupon interest	$	1,228	$	1,228	$	2,456	$	2,475
Amortization of deferred financing fees	188		188		376		377
Amortization of discount	3,282		3,040		6,502		6,051
Interest expense related to convertible notes	$	4,698	$	4,456	$	9,334	$	8,903