Subsequent Events (Details) $ in Millions |
3 Months Ended | 6 Months Ended |
|---|---|---|
|
Mar. 31, 2018
USD ($)
vessel
|
Jun. 30, 2018
vessel
|
|
| Subsequent Event [Line Items] | ||
| Number of T-ATS vessels | 1 | |
| Number of additional vessels | 7 | 7 |
| U.S. Navy | ||
| Subsequent Event [Line Items] | ||
| Construction in progress | $ | $ 63.6 |
| X | ||||||||||
- Definition Construction In Progress, Number Of Additional Vessels No definition available.
|
| X | ||||||||||
- Definition Construction In Progress, Number Of T-ATS Vessels No definition available.
|
| X | ||||||||||
- Definition Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. No definition available.
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| X | ||||||||||
- Details
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