Commitments and Contingencies (Details Textual) $ in Millions |
1 Months Ended | 3 Months Ended |
---|---|---|
May 31, 2017
parties
|
Mar. 31, 2018
USD ($)
|
|
Long-term Purchase Commitment [Line Items] | ||
Number of potentially responsible parties, environmental remediation | parties | 4 | |
Commitments related to development, redevelopment and capital improvement activities [Member] | ||
Long-term Purchase Commitment [Line Items] | ||
Commitments related to capital spending activities | $ | $ 160.0 | |
Time Period of Long-term Purchase Commitment | 12 months | |
Maximum [Member] | Commitments related to operations [Member] | ||
Long-term Purchase Commitment [Line Items] | ||
Time Period of Long-term Purchase Commitment | 1 year |