Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Aug. 31, 2013	Sep. 01, 2012	Aug. 31, 2013	Sep. 01, 2012
Sales and operating income data
Net sales	$ 178,287	$ 175,940	$ 357,598	$ 330,074
Operating income (loss)	9,358	7,553	15,472	9,870
Architectural Glass [Member]
Sales and operating income data
Net sales	69,974	63,277	144,777	122,342
Operating income (loss)	770	(2,018)	2,141	(4,424)
Architectural Services segment [Member]
Sales and operating income data
Net sales	42,177	46,653	88,653	85,571
Operating income (loss)	(787)	(1,019)	(1,752)	(3,598)
Architectural Framing Systems Segment [Member]
Sales and operating income data
Net sales	49,450	52,170	93,896	94,577
Operating income (loss)	5,180	6,066	7,244	9,162
Large-Scale Optical [Member]
Sales and operating income data
Net sales	19,745	19,571	39,218	38,829
Operating income (loss)	5,316	5,196	10,014	10,464
Intersegment eliminations [Member]
Sales and operating income data
Net sales	(3,059)	(5,731)	(8,946)	(11,245)
Corporate and other [Member]
Sales and operating income data
Operating income (loss)	$ (1,121)	$ (672)	$ (2,175)	$ (1,734)