Consolidated Statements Of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	12 Months Ended
	May 31, 2013	May 31, 2012	May 31, 2011
Net income (loss)	$ 24,550	$ 7,476	$ (64,913)
Other comprehensive income (loss)
Unrealized actuarial gains (losses) of defined benefit plans net of tax expense (benefit) or $3,126 and $1,568 and $102, respectively	5,432	(13,449)	178
Reclassification adjustment for losses (gains) benefit plans net of tax benefit (expense) of $409, $(200) and $697, respectively	712	1,713	1,210
Total other comprehensive income (loss)	6,144	(11,736)	1,388
Comprehensive income (loss)	$ 30,694	$ (4,260)	$ (63,525)