Fair Value Measurements - Cash Equivalents (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016
Assets:
Cash equivalents	$ 45	$ 143
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Cash equivalents	42	98
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money Market Funds
Assets:
Cash equivalents		100
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money Market Funds | Maximum
Assets:
Cash equivalents	100
Significant Other Observable Inputs (Level 2)
Assets:
Cash equivalents	3	45
Significant Other Observable Inputs (Level 2) | Certificates of Deposit | Maximum
Assets:
Cash equivalents	$ 100	$ 100