CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net loss	$ (5,401)	$ (6,187)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation	454	675
Depreciation and amortization	46	48
Loss on disposal of fixed assets	0	3
Loss from equity method investment	100	0
Amortization/accretion on marketable securities	(152)	(167)
Changes in operating assets and liabilities:
Prepaid and other current assets	(872)	(1,652)
Other assets	41	167
Accounts payable, accrued liabilities and other liabilities	(1,243)	(1,083)
Net cash used in operating activities	(7,027)	(8,196)
Cash flows from investing activities:
Purchase of marketable securities	(18,824)	(30,121)
Sale of marketable securities	25,360	34,410
Investment in Impilo Therapeutics	(100)	0
Net cash provided by investing activities	6,436	4,289
Cash flows from financing activities:
Tax withholding payments on net share settlement equity awards	(142)	(85)
Net cash used in financing activities	(142)	(85)
Effect of exchange rate changes on cash	(55)	(7)
Net decrease in cash and cash equivalents	(788)	(3,999)
Cash and cash equivalents at beginning of period	22,593	32,154
Cash and cash equivalents at end of period	$ 21,805	$ 28,155

Increase Decrease In Accounts Payable Accrued Expenses And Other Liabilities

No definition available.

Name:	lsta_IncreaseDecreaseInAccountsPayableAccruedExpensesAndOtherLiabilities
Namespace Prefix:	lsta_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.