Acquisition of Chingis (Narrative) (Details) (USD $)	3 Months Ended														12 Months Ended			0 Months Ended	1 Months Ended		12 Months Ended			12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 14, 2012 Chingis	May 31, 2013 Chingis	Sep. 30, 2012 Chingis	Sep. 30, 2014 Chingis	Sep. 14, 2012 Chingis	Sep. 30, 2012 Chingis Selling, general and administrative	Sep. 30, 2014 Chingis Developed technology	Sep. 30, 2014 Chingis Customer relationships	Sep. 30, 2014 Chingis Other intangibles
Business Acquisition [Line Items]
Percentage of equity acquired																						94.10%
Total purchase price																		$ 31,800,000
Investment in consolidated subsidiaries, net of cash and cash equivalents acquired															0	0	13,210,000	13,200,000
Cash on acquired entity's balance sheet																		18,600,000
Estimated useful lives of purchased definite lived intangible assets																								6 years	6 years	3 years
Costs related to acquisition																							400,000
Revenue																				1,200,000
Net loss	(2,858,000)	(6,227,000)	[1]	(8,958,000)	[2]	(5,446,000)	[3]	(4,730,000)	[4]	(7,246,000)	[5]	(3,280,000)	[6]	(2,488,000)	(23,489,000)	(17,744,000)	2,605,000			1,200,000
Additional ownership percentage acquired																			4.80%		1.10%
Acquisition price for additional interest acquired															$ 388,000	$ 1,614,000	$ 2,370,000		$ 1,600,000		$ 400,000
Ownership percentage																					100.00%

[1] In the June 2014 quarter, the Company realized a gain of $2.1 million from the sale of its remaining freely-tradeable shares of Nanya common stock.

[2] In the March 2014 quarter, the Company realized a gain from the sale of investments of $6.0 million including $3.9 million from the sale of a portion of its shares of Nanya common stock and $2.1 million from the sale of its remaining shares of SMIC common stock.

[3] In the December 2013 quarter, the Company realized a gain of $3.1 million from the sale of a portion of its shares of Nanya common stock.

[4] In the September 2013 quarter, the Company realized a gain of $2.9 million from the sale of a portion of its shares of Nanya common stock.

[5] In the June 2013 quarter, the Company realized a gain from the sale of investments of $7.3 million including $7.0 million from the sale of a portion of its shares of Nanya common stock.

[6] In the March 2013 quarter, the Company realized a gain of $2.1 million from the sale of a portion of its shares of Nanya common stock.