Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Line Items]
Uncertain tax positions reasonably possible to reverse in next twelve months	$ 3,200
Accrued interest and penalties	500	$ 400
Limit on operating loss carryforwards and recognition	11,400
Limit on operating loss carryforwards and recognition, tax-effected	4,000
Total deferred tax assets	459,304
Deferred tax liabilities	(43,496)
Net deferred tax assets before valuation allowance	415,808
Valuation allowance	(415,762)	$ (445,200)
Net deferred tax assets	46
Subject To Annual Limitation
Income Tax Disclosure [Line Items]
Total deferred tax assets	93,741
Generally Not Subject to Annual Limitation
Income Tax Disclosure [Line Items]
Total deferred tax assets	$ 365,563