XML 108 R91.htm IDEA: XBRL DOCUMENT v3.3.1.900
Benefit Plans (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Defined Contribution Plan Disclosure [Line Items]      
Incurred expense related to savings and retirement plans $ 7.0 $ 6.0 $ 5.1
Incurred expense related to non qualified deferred compensation plans 0.4 0.3 0.4
ProAssurance deferred compensation liabilities total $ 14.9 $ 14.0 $ 13.1
Minimum [Member]      
Defined Contribution Plan Disclosure [Line Items]      
Percentage of benefit plan contribution by employer 5.00%    
Maximum [Member]      
Defined Contribution Plan Disclosure [Line Items]      
Percentage of benefit plan contribution by employer 10.00%