Adaptimmune Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Available-for-sale debt securities (Details)

v3.19.3

Available-for-sale debt securities (Details) $ in Thousands	Sep. 30, 2019 USD ($) security	Dec. 31, 2018 USD ($) security
Schedule of Available-for-sale Securities [Line Items]
Fair market value of investments in an unrealized loss position	$ 7,200	$ 117,200
Number of debt securities \| security	3	37
Number of available-for-sale securities in an unrealized loss position for more than one year \| security	0
Cash equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 19,157
Aggregate estimated fair value	19,157
Marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	63,396
Gross unrealized gains	57
Gross unrealized losses	(2)
Aggregate estimated fair value	63,451
Corporate Debt Securities Maturity Period Less Than Three Months \| Marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	24,670
Gross unrealized gains	10
Aggregate estimated fair value	24,680
Money Market Funds Maturity Period Less Than Three Months \| Cash equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	19,157
Aggregate estimated fair value	19,157
Corporate Debt Securities Maturity Period Three Months To One Year \| Marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	34,707
Gross unrealized gains	45
Gross unrealized losses	(2)
Aggregate estimated fair value	34,750
Agency Bond Maturity Period Three Months To One Year \| Marketable securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	4,019
Gross unrealized gains	2
Aggregate estimated fair value	$ 4,021

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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