Inventories - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Gross tooling inventory	$ 17.0	$ 10.3
Tooling inventory net of progress billings	$ 15.4	$ 9.4

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