| Component: (Network and Table) | |
|---|---|
| Network | 100910 - Disclosure - Retirement Plans - Weighted-Average Assumptions Used to Determine Net Benefit Obligation (Detail) (http://www.lsccom.com/20161231/taxonomy/role/DisclosureRetirementPlansWeightedAverageAssumptionsUsedToDetermineNetBenefitObligationDetail) |
| Table | Schedule Of Defined Benefit Plans Disclosures [Table] |
| Reporting Entity [Axis] | 0001669812 (http://www.sec.gov/CIK) |
| Defined Benefit Plans and Other Postretirement Benefit Plans | Pension Benefits |
| Defined Benefit Plan Disclosure [Line Items] | Period [Axis] | |||
|---|---|---|---|---|
2016-12-31 | 2015-12-31 | |||
| Defined Contribution Plan Name | Defined Contribution Plan Name | |||
| Qualified | Non-Qualified & International | Qualified | Non-Qualified & International | |
Discount rate | ||||