Available with Standard or Advanced license.
You can split selected lines where they intersect using Planarize Lines 
on the Advanced Editing toolbar. 
When Planarize is used on a multipart line feature, it is split at the point of intersection into a new feature.
- Click the Edit tool
on the Editor toolbar.
- Select the line features you want to split at intersections.
- Click Planarize Lines on the Advanced Editing toolbar.
- Optionally, type a cluster tolerance.
- Click OK.
The selected lines are split into new features where they intersect. Planarize also removes overlapping line segments—such as those created by constructing lines from polygons that have shared boundaries.