XML 49 R37.htm IDEA: XBRL DOCUMENT v3.10.0.1
Revenue Recognition Revenue Recognition (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Disaggregation of Revenue [Line Items]          
Percentage of Revenue, previously constrained 5.00%        
Contract with Customer, Asset, Net $ 310.0   $ 310.0   $ 236.0
Contract with Customer, Liability 87.2   $ 87.2   $ 73.7
Percentage of Revenue, Remaining Performance Obligation     5.00%    
Out of Scope of Topic 606 Revenue [Member]          
Disaggregation of Revenue [Line Items]          
Fees and Commissions, Mortgage Banking and Servicing $ 35.0 $ 16.0 $ 66.0 $ 51.0