XML 30 R20.htm IDEA: XBRL DOCUMENT
v3.22.2

Investments (Tables) | 9 Months Ended
--- | ---
Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract] |
Summary of Short-term and Long-term Investments and Marketable Securities | The following tables summarize the Company’s short-term and long-term investments and marketable securities as of June 30, 2022 and September 30, 2021 by measurement category:
| As of June 30, 2022
| (In thousands)
| Cost Basis |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value
Classified as Cash Equivalents |  |  |  |  |  |  |
Commercial notes (due within ninety days) | $ | 25,325 |  |  | $ | 11 |  |  | $ | — |  |  | $ | 25,336 |
Classified as Held to Maturity |  |  |  |  |  |  |
Commercial notes (due within one year) | $ | 227,057 |  |  | $ | 21 |  |  | $ | (1,588) |  |  | $ | 225,490 |
Commercial notes (due within one through three years) | $ | 165,920 |  |  | $ | — |  |  | $ | (6,380) |  |  | $ | 159,540 |
Certificate of deposit (due within one year) | $ | 50,000 |  |  | $ | — |  |  | $ | — |  |  | $ | 50,000 |
Classified as Marketable Securities |  |  |  |  |  |  |
Marketable securities | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Total | $ | 468,302 |  |  | $ | 32 |  |  | $ | (7,968) |  |  | $ | 460,366 |
| As of September 30, 2021
| (In thousands)
| Cost Basis |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value
Classified as Held to Maturity |  |  |  |  |  |  |
Commercial notes (due within one year) | $ | 56,627 |  |  | $ | 803 |  |  | $ | — |  |  | $ | 57,430 |
Commercial notes (due within one through three years) | $ | 195,595 |  |  | $ | 1,151 |  |  | $ | (103) |  |  | $ | 196,643 |
Certificate of deposit (due within one through two years) | $ | 50,000 |  |  | $ | — |  |  | $ | — |  |  | $ | 50,000 |
Classified as Marketable Securities |  |  |  |  |  |  |
Marketable securities | $ | 127,481 |  |  | $ | — |  |  | $ | (753) |  |  | $ | 126,728 |
Total | $ | 429,703 |  |  | $ | 1,954 |  |  | $ | (856) |  |  | $ | 430,801 |

X
- Definition Held to maturity securities and marketable securities. + References No definition available. + Details
Name: | arwr_HeldToMaturitySecuritiesAndMarketableSecuritiesTableTableTextBlock
Namespace Prefix: | arwr_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration