Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Narrative (Details)

v3.19.1
Stock-Based Compensation - Narrative (Details) - Performance stock units - shares
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Dec. 31, 2018
2018 Performance Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Equity instruments other options, outstanding (in shares)     147,741
Equity instruments other than options, vested (in shares) 98,492    
Award vesting rights, percentage 100.00%    
2017 Performance Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Equity instruments other options, outstanding (in shares)     140,493
Equity instruments other than options, vested (in shares)   116,168  
Shares issued (in shares)   25,726  
Award vesting rights, percentage   22.10%