INVENTORIES - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Net tooling inventory	$ 3.2	$ 2.8

The net amount of tooling inventory after the deduction of progress billings as of the balance sheet date.

No definition available.

Name:	ldl_ToolingInventoryNetOfProgressBillings
Namespace Prefix:	ldl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant