Fair Value Measurements - Notes (Details) - Notes $ in Thousands	Sep. 30, 2015 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	$ 22,430
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	22,430
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
2033 Senior Notes	$ 25,238