v3.19.3.a.u2
Leases - Real estate and equipment (Details)
$ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
item
Jan. 01, 2019
Operating Lease Commitments    
Number of properties subleased | item 1  
Rate used to determine lease liabilities at implementation date   3.75%
Operating Lease, Liability | $ $ 6.8  
Weighted average in months 3 years 6 months