v2.4.1.9

Debt - Additional Information (Detail) (USD $) | 0 Months Ended | 1 Months Ended | 3 Months Ended | 12 Months Ended | 1 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 22, 2014 | Aug. 31, 2012 | Jul. 22, 2014 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Apr. 30, 2012 Debt_Instruments | Apr. 17, 2014 | Dec. 31, 2011 | Aug. 31, 2013
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Loan and security agreement cost |  | $ 15,000,000us-gaap_DebtInstrumentFaceAmount |  |  |  |  |  |  |  |
Total repayment of principal |  | 10,333,833us-gaap_DebtInstrumentPeriodicPaymentPrincipal |  |  |  |  |  |  |  |
Termination fee paid |  | 875,000cdna_DebtInstrumentTerminationFeeAmount |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  | 628,000us-gaap_InterestExpenseDebt |  |  |  |
Net cash proceeds from loan |  | 3,432,260us-gaap_ProceedsFromIssuanceOfDebt |  |  |  |  |  |  |  |
Loan deferral additional fee |  |  |  | 150,000us-gaap_DebtInstrumentCollateralFee |  |  |  |  |  |
Loan to defer the beginning of principal repayment |  |  |  | Mar. 01, 2014 |  |  |  |  |  |
Interest payment |  |  |  | 566,822us-gaap_DebtInstrumentPeriodicPayment |  |  |  |  |  |
Annual interest rate |  |  |  | 9.95%us-gaap_DebtInstrumentInterestRateStatedPercentage |  |  |  |  |  |
Final payment due at the end of the term |  |  |  | 1,275,000us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid |  |  |  |  |  |
Facility Fee amount |  |  |  | 75,000us-gaap_DebtInstrumentFeeAmount |  |  |  |  |  |
Loan interest description |  |  |  | Interest-only payments for 18 months followed by 30 equal monthly principal and interest payments |  |  |  |  |  |
Estimated fair value of warrants |  |  |  | (1,464,000)us-gaap_FairValueAdjustmentOfWarrants | 525,000us-gaap_FairValueAdjustmentOfWarrants | (2,000)us-gaap_FairValueAdjustmentOfWarrants |  |  |  |
Initial Public offering, closing date |  |  |  | Jul. 22, 2014 |  |  |  |  |  |
Shares issued upon conversion | 510,777us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities |  |  |  |  |  |  |  |  |
Amortization of debt discount |  |  | 256,000cdna_AmortizationOfDebtDiscount |  |  |  |  |  |  |
Extinguishment of embedded derivative |  |  |  | 120,000us-gaap_EmbeddedDerivativeFairValueOfEmbeddedDerivativeLiability |  |  |  |  |  |
Illumina, Inc. [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Annual interest rate |  |  |  |  |  |  |  | 8.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / dei_LegalEntityAxis = cdna_IlluminaIncMember |  |
Subordinated convertible promissory note issued |  |  |  |  |  |  |  | 5,000,000us-gaap_ConvertibleSubordinatedDebt / dei_LegalEntityAxis = cdna_IlluminaIncMember |  |
Subordinated convertible promissory note maturity term |  |  |  | 1 year |  |  |  |  |  |
Subordinated Convertible Promissory Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Annual interest rate |  |  |  |  |  |  |  |  | 7.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_ShortTermDebtTypeAxis = cdna_SubordinatedConvertiblePromissoryNotesMember |
Principal amount of notes |  |  |  |  |  |  |  |  | 11,365,000cdna_ConvertibleSubordinatedNotesPrincipalAmount / us-gaap_ShortTermDebtTypeAxis = cdna_SubordinatedConvertiblePromissoryNotesMember |
Amortization of debt discount |  |  |  |  |  | 39,000us-gaap_AmortizationOfDebtDiscountPremium / us-gaap_ShortTermDebtTypeAxis = cdna_SubordinatedConvertiblePromissoryNotesMember |  |  |  |
Series G Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase stock of convertible preferred stock, shares |  |  |  |  |  |  | 357,216us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |
Warrants to purchase stock of convertible preferred stock, per share |  |  |  |  |  |  | $ 21.78us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |
Principal and interest amount of notes |  |  |  |  |  |  | 12,423,000us-gaap_ConvertibleNotesPayable / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |
Convertible notes, shares |  |  |  |  |  |  | 570,294us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |
Convertible notes, per share |  |  |  |  |  |  | $ 21.78us-gaap_DebtInstrumentConvertibleConversionPrice1 / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |
2012 Loan [Member] | Series G Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase stock of convertible preferred stock, shares |  |  |  |  |  |  |  |  |  | 167,182us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandTwelveTermLoanMember / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember
Warrants to purchase stock of convertible preferred stock, per share |  |  |  |  |  |  |  |  |  | $ 21.78us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandTwelveTermLoanMember / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember
Warrants exercisable period |  |  |  | The warrants are exercisable until 2019 |  |  |  |  |  |
2010 Loan [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Amortization expense |  |  |  |  |  | 4,400us-gaap_AmortizationOfFinancingCosts / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandAndTenTermLoanMember |  |  |  |
2010 Loan [Member] | Series G Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase stock of convertible preferred stock, shares |  |  |  | 17,215us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandAndTenTermLoanMember / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |  |  |  |
Warrants to purchase stock of convertible preferred stock, per share |  |  |  | $ 21.78us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandAndTenTermLoanMember / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |  |  |  |
Warrants exercisable period |  |  |  | The warrants were exercisable until 2017 |  |  |  |  |  |
Estimated fair value of warrants |  |  |  | $ 8,000us-gaap_FairValueAdjustmentOfWarrants / us-gaap_LongtermDebtTypeAxis = cdna_TwoThousandAndTenTermLoanMember / us-gaap_StatementClassOfStockAxis = cdna_SeriesGConvertiblePreferredStockMember |  |  |  |  |  |

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- Definition Convertible Subordinated Notes Principal Amount + References No definition available. + Details
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- Definition Debt instrument termination fee amount. + References No definition available. + Details
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- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 + Details
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- Definition Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 8 -Article 9 + Details
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- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Subparagraph 2 -Article 4 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 + Details
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- Definition Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX210.5-02.22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Article 5 -Subsection 20, 22 + Details
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- Definition Amount of fees associated with providing collateral for the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 + Details
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- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870 + Details
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- Definition The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format. + 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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 + Details
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- Definition Amount of the fee that accompanies borrowing money under the debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -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 210.5-02.22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Description of the frequency of periodic payments (monthly, quarterly, annual). + 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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of the required periodic payments including both interest and principal payments. + 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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition Amount of the required periodic payments applied to principal. + 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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 + Details
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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