Summary of Significant Accounting Policies Fair Value Measurements Policy Additional Information (Details) (Fair Value, Inputs, Level 1 [Member], USD $) In Thousands	Sep. 30, 2011
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 0
Liabilities, Fair Value Disclosure	$ 0