Organization and Significant Accounting Policies (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Schedule of Available-for-sale Securities [Line Items]
Accumulated foreign currency translation adjustments	$ 6,048	$ 2,116
Accumulated net retirement plan transition asset (net of tax of $119 in 2012)	115	311
Accumulated net retirement plan transition asset, tax	119	0
Accumulated net retirement plan actuarial losses (net of tax of $323 in 2012)	(2,241)	(2,466)
Accumulated net retirement plan actuarial gains (losses), tax	323	0
Total accumulated other comprehensive income (loss)	2,399	(1,252)
SMIC
Schedule of Available-for-sale Securities [Line Items]
Accumulated net unrealized loss, net of tax	0	(1,213)
Accumulated net unrealized loss, tax	0	716
Nanya
Schedule of Available-for-sale Securities [Line Items]
Accumulated net unrealized loss, net of tax	(1,523)	0
Accumulated net unrealized loss, tax	$ 312	$ 0