Basis of Presentation (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($) item	Jul. 01, 2017 USD ($)
Net proceeds from corporate-owned life insurance policies	$ 98	$ 22
Number of borrowing groups \| item	2
ASU 2016-15
Net proceeds from corporate-owned life insurance policies		22
Net proceeds from corporate-owned life insurance policies reclassified from operating activities		$ (22)

Amount of net cash inflow for proceeds from settlement of corporate-owned life insurance policy, net of premiums paid classified as investing activities. Includes, but is not limited to, bank-owned life insurance policy.

No definition available.

Name:	txt_NetProceedsFromLifeInsurancePolicy
Namespace Prefix:	txt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration