XML 17 R39.htm IDEA: XBRL DOCUMENT
v2.4.1.9

FAIR VALUE MEASUREMENTS (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Included in cash and cash equivalents |  |
Amortized Cost | $ 40,342us-gaap_CashEquivalentsAtCarryingValue | $ 10,285us-gaap_CashEquivalentsAtCarryingValue
Estimated Fair Value | 40,342us-gaap_CashAndCashEquivalentsFairValueDisclosure | 10,285us-gaap_CashAndCashEquivalentsFairValueDisclosure
Restricted cash |  |
Amortized Cost | 266us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue | 795us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Estimated Fair Value | 266us-gaap_RestrictedInvestmentsAtFairValue | 795us-gaap_RestrictedInvestmentsAtFairValue
Marketable securities |  |
Amortized Cost | 127,661us-gaap_AvailableForSaleSecuritiesAmortizedCost | 52,248us-gaap_AvailableForSaleSecuritiesAmortizedCost
Gross Unrealized Gains | 16gern_GrossUnrealizedGainsAvailableForSaleSecurities | 5gern_GrossUnrealizedGainsAvailableForSaleSecurities
Gross Unrealized Losses | (100)gern_GrossUnrealizedLossesAvailableForSaleSecurities | (19)gern_GrossUnrealizedLossesAvailableForSaleSecurities
Estimated Fair Value | 127,577us-gaap_AvailableForSaleSecurities | 52,234us-gaap_AvailableForSaleSecurities
Money market funds |  |
Included in cash and cash equivalents |  |
Amortized Cost | 40,342us-gaap_CashEquivalentsAtCarryingValue / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember | 8,079us-gaap_CashEquivalentsAtCarryingValue / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember
Estimated Fair Value | 40,342us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember | 8,079us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_InvestmentTypeAxis = us-gaap_MoneyMarketFundsMember
Corporate notes |  |
Included in cash and cash equivalents |  |
Amortized Cost |  | 2,206us-gaap_CashEquivalentsAtCarryingValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateNoteSecuritiesMember
Estimated Fair Value |  | 2,206us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_InvestmentTypeAxis = us-gaap_CorporateNoteSecuritiesMember
Certificates of deposit |  |
Restricted cash |  |
Amortized Cost | 266us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember | 795us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember
Estimated Fair Value | 266us-gaap_RestrictedInvestmentsAtFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember | 795us-gaap_RestrictedInvestmentsAtFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CertificatesOfDepositMember
Government-sponsored enterprise securities (due in less than 1 year) |  |
Marketable securities |  |
Amortized Cost | 401us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember | 7,369us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember
Gross Unrealized Gains |  | 1gern_GrossUnrealizedGainsAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember
Gross Unrealized Losses | (1)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember | (1)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember
Estimated Fair Value | 400us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember | 7,369us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember
Government-sponsored enterprise securities (due in 1 to 2 years) |  |
Marketable securities |  |
Amortized Cost | 6,556us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_GovernmentSponsoredEnterpriseSecuritiesDueInOneToTwoYearsMember |
Gross Unrealized Losses | (7)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_GovernmentSponsoredEnterpriseSecuritiesDueInOneToTwoYearsMember |
Estimated Fair Value | 6,549us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_GovernmentSponsoredEnterpriseSecuritiesDueInOneToTwoYearsMember |
Commercial paper (due in less than 1 year) |  |
Marketable securities |  |
Amortized Cost | 10,985us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember | 5,496us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember
Gross Unrealized Gains | 14gern_GrossUnrealizedGainsAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember | 3gern_GrossUnrealizedGainsAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember
Estimated Fair Value | 10,999us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember | 5,499us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CommercialPaperDueInLessThanOneYearMember
Corporate notes (due in less than 1 year) |  |
Marketable securities |  |
Amortized Cost | 97,307us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember | 39,383us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember
Gross Unrealized Gains | 2gern_GrossUnrealizedGainsAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember | 1gern_GrossUnrealizedGainsAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember
Gross Unrealized Losses | (63)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember | (18)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember
Estimated Fair Value | 97,246us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember | 39,366us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInLessThanOneYearMember
Corporate notes (due in 1 to 2 years) |  |
Marketable securities |  |
Amortized Cost | 12,412us-gaap_AvailableForSaleSecuritiesAmortizedCost / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInOneToTwoYearsMember |
Gross Unrealized Losses | (29)gern_GrossUnrealizedLossesAvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInOneToTwoYearsMember |
Estimated Fair Value | $ 12,383us-gaap_AvailableForSaleSecurities / us-gaap_InvestmentTypeAxis = gern_CorporateNoteSecuritiesDueInOneToTwoYearsMember |

X
- Definition Amount of gross unrealized gains from available-for-sale securities as of the reporting date. + References No definition available. + Details
Name: | gern_GrossUnrealizedGainsAvailableForSaleSecurities
Namespace Prefix: | gern_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of gross unrealized losses from available-for-sale securities as of the reporting date. + References No definition available. + Details
Name: | gern_GrossUnrealizedLossesAvailableForSaleSecurities
Namespace Prefix: | gern_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_AvailableForSaleSecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_CashAndCashEquivalentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
Name: | us-gaap_CashAndCashEquivalentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RestrictedCashAndInvestmentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate value of all restricted investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-12C.9(c)) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611225-123010 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12.6(c)) -URI http://asc.fasb.org/extlink&oid=34726532&loc=d3e611133-123010 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12C -Paragraph 9 -Subparagraph c -Article 12 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 12 -Paragraph 6 -Subparagraph c -Article 12 + Details
Name: | us-gaap_RestrictedInvestmentsAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_InvestmentTypeAxis=gern_CommercialPaperDueInLessThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=gern_CorporateNoteSecuritiesDueInLessThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=gern_CorporateNoteSecuritiesDueInOneToTwoYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=gern_GovernmentSponsoredEnterpriseSecuritiesDueInOneToTwoYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=gern_USGovernmentSponsoredEnterprisesDebtSecuritiesDueInLessThanOneYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CorporateNoteSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_MoneyMarketFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |