XML 42 R75.htm IDEA: XBRL DOCUMENT v3.19.3
Long-Term Debt (Narrative) (Details) - USD ($)
shares in Thousands
1 Months Ended
Oct. 01, 2019
Oct. 31, 2019
Sep. 30, 2019
Aug. 31, 2019
Debt Instrument [Line Items]        
Debt issued     $ 1,450,000,000  
Subsequent event | Stock Purchase Contract, 2016 Series C Equity Units Subject to Mandatory Redemption        
Debt Instrument [Line Items]        
Shares of common stock issued under stock purchase contracts (in shares) 5,870      
Senior Notes | 2016 Series D 1.5% Senior Notes | Subsequent event | DTE Energy        
Debt Instrument [Line Items]        
Interest rate   1.50%    
Securities redeemed at maturity   $ 400,000,000    
Senior Notes | Series C, 1.5% RSNs due 2024        
Debt Instrument [Line Items]        
Debt issued       $ 675,000,000
Interest rate       1.50%
Senior Notes | Series C, Remarketed, 2.529% RSN due 2024 | Subsequent event        
Debt Instrument [Line Items]        
Interest rate 2.529%      
DTE Gas | Mortgage Bonds | October 2019 2.95% First Mortgage Bonds Maturing 2029 | Subsequent event        
Debt Instrument [Line Items]        
Debt issued   $ 140,000,000    
Interest rate   2.95%    
DTE Gas | Mortgage Bonds | October 2019 3.72% First Mortgage Bonds Maturing 2049 | Subsequent event        
Debt Instrument [Line Items]        
Debt issued   $ 140,000,000    
Interest rate   3.72%    
DTE Gas | Senior Notes | 2004 Series E 5.0% Senior Notes | Subsequent event        
Debt Instrument [Line Items]        
Interest rate   5.00%    
Securities redeemed at maturity   $ 120,000,000