Fair Value Measurements (Details) (USD $) | Mar. 31, 2014 | Dec. 31, 2013 |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Available-for-sale Securities | $103,000 | $103,000 |
Carrying (Reported) Amount, Fair Value Disclosure [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 37,878,000 | ' |
Marketable Securities, Fair Value Disclosure | 2,203,000 | ' |
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 | 37,878,000 | ' |
Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Cash and Cash Equivalents, Fair Value Disclosure | 37,878,000 | ' |
Marketable Securities, Fair Value Disclosure | 2,203,000 | ' |
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 | 48,000 | ' |
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 | 48,000 | ' |
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 | 48,000 | ' |
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 | 55,000 | ' |
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 | 55,000 | ' |
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | ' | ' |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ' | ' |
Marketable Securities, Fair Value Disclosure | 55,000 | ' |
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 | 1,477,000 | ' |
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 | 1,477,000 | ' |
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 | 1,477,000 | ' |
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 | 623,000 | ' |
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 | 623,000 | ' |
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 | 623,000 | ' |
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 | 8,557,000 | ' |
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 | 8,557,000 | ' |
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 | 8,557,000 | ' |
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 | 29,321,000 | ' |
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 | 29,321,000 | ' |
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 | $29,321,000 | ' |