Accounts payable and accrued expenses related parties current.

No definition available.

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Namespace Prefix:	phat_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Agreement extends period for termination.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Related Party Transactions - Additional Information (Details) - USD ($)		3 Months Ended
	May 05, 2020	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		$ 17,000,000		$ 15,000,000
Commercial Supply and Temporary Services Agreement
Related Party Transaction [Line Items]
Minimum purchase obligation		0
Commercial Supply Agreement
Related Party Transaction [Line Items]
Agreement extends period for termination	2 years
PCI Pharma Services
Related Party Transaction [Line Items]
Expense related to services		3,000,000	$ 0
PCI Pharma Services \| Clinical Manufacturing Services
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		1,200,000		1,100,000
Expense related to services		100,000	300,000
Takeda \| Commercial Supply and Temporary Services Agreement
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		1,500,000		$ 1,400,000
Expense related to services		$ 100,000	$ 1,100,000