Fair Value Measurements - Notes (Details) (Notes, USD $) In Thousands, unless otherwise specified	Sep. 30, 2014
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	$ 66,154
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	66,154
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	$ 64,440