XML 32 R19.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Investments (Tables) | 3 Months Ended
--- | ---
Dec. 31, 2021
Held To Maturity Securities Classified [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 December 31, 2021 and September 30, 2021 by measurement category:
Held to Maturity |  | As of December 31, 2021 |  |  |
|  | (In thousands) |  |  |
|  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |  |  |
Commercial notes (due within one year) |  | $ | 62,537 |  |  | $ | 687 |  |  | $ | - |  |  | $ | 63,224 |  |  |
Commercial notes (due within one through three years) |  | $ | 217,572 |  |  | $ | 381 |  |  | $ | (1,374 | ) |  | $ | 216,579 |  |  |
Certificate of deposit (due within one year) |  | $ | 50,000 |  |  | $ | - |  |  | $ | - |  |  | $ | 50,000 |  |  |
Total |  | $ | 330,109 |  |  | $ | 1,068 |  |  | $ | (1,374 | ) |  | $ | 329,803 |  |  |
|  | As of September 30, 2021 |  |  |
|  | (In thousands) |  |  |
|  | Amortized Cost |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |  |  |
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 two years) |  | $ | 50,000 |  |  | $ | - |  |  | $ | - |  |  | $ | 50,000 |  |  |
Total |  | $ | 302,222 |  |  | $ | 1,954 |  |  | $ | (103 | ) |  | $ | 304,073 |  |  |
Fair Value |  | As of December 31, 2021 |
|  | (In thousands) |
|  | Cost |  |  | Realized Gains/(Losses) |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
Marketable securities |  | $ | 125,000 |  |  | $ | 3,134 |  |  | $ | - |  |  | $ | (2,124 | ) |  | $ | 126,010 |
Total |  | $ | 125,000 |  |  | $ | 3,134 |  |  | $ | - |  |  | $ | (2,124 | ) |  | $ | 126,010 |
|  | As of September 30, 2021 |
|  | (In thousands) |
|  | Cost |  |  | Realized Gains/(Losses) |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
Marketable securities |  | $ | 125,000 |  |  | $ | 2,481 |  |  | $ | 135 |  |  | $ | (888 | ) |  | $ | 126,728 |
Total |  | $ | 125,000 |  |  | $ | 2,481 |  |  | $ | 135 |  |  | $ | (888 | ) |  | $ | 126,728 |

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

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