Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	$ 1	$ 1
Total short-term investments	63	129
Total financial assets measured at fair value	64	130
Commodities Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	6	6
Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	1	1
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	34
Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	23	123
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	1	1
Total short-term investments	0	0
Total financial assets measured at fair value	1	1
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	1	1
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Commodities Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	0	0
Total short-term investments	63	129
Total financial assets measured at fair value	63	129
Significant Other Observable Inputs (Level 2) [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	0	0
Significant Other Observable Inputs (Level 2) [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	34
Significant Other Observable Inputs (Level 2) [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	23	123
Significant Other Observable Inputs (Level 2) [Member] | Commodities Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	6	6
Significant Unobserved Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	0	0
Total short-term investments	0	0
Total financial assets measured at fair value	0	0
Significant Unobserved Inputs (Level 3) [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash equivalents	0	0
Significant Unobserved Inputs (Level 3) [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Significant Unobserved Inputs (Level 3) [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Significant Unobserved Inputs (Level 3) [Member] | Commodities Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	$ 0	$ 0