Fair Value Measurements (Details) (USD $) | Sep. 30, 2013 | Dec. 31, 2012 |
In Thousands, unless otherwise specified |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Available-for-sale Securities | $96 | $92 |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 49,627 | ' |
Marketable Securities, Fair Value Disclosure | 2,288 | ' |
Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 49,627 | ' |
Marketable Securities, Fair Value Disclosure | 2,288 | ' |
Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 49,627 | ' |
Marketable Securities, Fair Value Disclosure | 2,288 | ' |
Money Market Funds [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
Money Market Funds [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
Mutual Funds [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
Mutual Funds [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 48 | ' |
US Treasury Securities [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 1,370 | ' |
US Treasury Securities [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 1,370 | ' |
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 1,370 | ' |
US Government Agencies Securities [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 822 | ' |
US Government Agencies Securities [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 822 | ' |
US Government Agencies Securities [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 822 | ' |
Cash [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 12,303 | ' |
Cash [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 12,303 | ' |
Cash [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 12,303 | ' |
Money Market Funds [Member] | Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 37,324 | ' |
Money Market Funds [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 37,324 | ' |
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | $37,324 | ' |