Quarterly report pursuant to Section 13 or 15(d)

Contingencies (Details)

v3.7.0.1
Contingencies (Details) - Pending Litigation
$ in Millions
Mar. 31, 2017
USD ($)
contract
lawsuit
SJGC  
Contingencies  
Number of lawsuits | lawsuit 2
Number of long term gas contracts | contract 2
WGL  
Contingencies  
Number of long term gas contracts | contract 2
WGL | Minimum  
Contingencies  
Damages sought | $ $ 30.0
Potential Positive Outcome of Litigation | SJGC  
Contingencies  
Additional accounts receivable | $ $ 56.0