Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statement Of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2011	Nov. 30, 2010
Net sales	$ 156,071	$ 148,111	$ 337,811	$ 320,233
Cost of products sold	153,325	136,044	321,240	292,058
Gross profit	2,746	12,067	16,571	28,175
Selling, general and administrative	13,877	18,543	31,681	34,684
Restructuring charges	3,216		3,216
Interest	8,838	13,886	18,298	28,297
Loss on debt retirements		613		29,619
Other income	(1,527)	(1,929)	(7,399)	(6,819)
TOTAL EXPENSES	24,404	31,113	45,796	85,781
Income (loss) before the following items	(21,658)	(19,046)	(29,225)	(57,606)
Income taxes (benefit)	(621)	(7,845)	(768)	(22,713)
Net income (loss) before equity in earnings (loss) of subsidiaries	(21,037)	(11,201)	(28,457)	(34,893)
Net income (loss)	(21,037)	(11,201)	(28,457)	(34,893)
Texas Industries, Inc. [Member]
Selling, general and administrative	228	2,107	1,253	2,767
Interest	17,008	17,269	34,265	31,634
Loss on debt retirements		613		29,619
Other income	(14)	(83)	(27)	(126)
TOTAL EXPENSES	16,349	19,033	33,736	62,139
Intercompany other income	(873)	(873)	(1,755)	(1,755)
Income (loss) before the following items	(16,349)	(19,033)	(33,736)	(62,139)
Income taxes (benefit)	(1,404)	(6,749)	(3,534)	(22,909)
Net income (loss) before equity in earnings (loss) of subsidiaries	(14,945)	(12,284)	(30,202)	(39,230)
Equity in earnings (loss) of subsidiaries	(6,092)	1,083	1,745	4,337
Net income (loss)	(21,037)	(11,201)	(28,457)	(34,893)
Guarantor Subsidiaries [Member]
Net sales	156,071	148,111	337,811	320,233
Cost of products sold	153,325	136,044	321,240	292,058
Gross profit	2,746	12,067	16,571	28,175
Selling, general and administrative	13,649	16,436	30,428	31,917
Restructuring charges	3,216		3,216
Other income	(1,513)	(1,846)	(7,372)	(6,693)
TOTAL EXPENSES	8,055	12,080	12,060	23,642
Intercompany other income	(7,297)	(2,510)	(14,212)	(1,582)
Income (loss) before the following items	(5,309)	(13)	4,511	4,533
Income taxes (benefit)	783	(1,096)	2,766	196
Net income (loss) before equity in earnings (loss) of subsidiaries	(6,092)	1,083	1,745	4,337
Net income (loss)	(6,092)	1,083	1,745	4,337
Consolidating Adjustments [Member]
Interest	(8,170)	(3,383)	(15,967)	(3,337)
Intercompany other income	8,170	3,383	15,967	3,337
Equity in earnings (loss) of subsidiaries	6,092	(1,083)	(1,745)	(4,337)
Net income (loss)	$ 6,092	$ (1,083)	$ (1,745)	$ (4,337)