Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans - Fair Values of Plan Assets by Major Asset Category (Details)

v3.10.0.1
Employee Benefit Plans - Fair Values of Plan Assets by Major Asset Category (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets $ 5,313 $ 5,356 $ 4,937
Cash and cash equivalents — money markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 407 165  
Equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 813 670  
Equity funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,448 2,468  
Fixed income funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,645 2,053  
Quoted Prices in Active Markets for Identical Assets (Level 1)      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 5,313 5,356  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and cash equivalents — money markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 407 165  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 813 670  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 2,448 2,468  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed income funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 1,645 2,053  
Significant Other Observable Inputs (Level 2)      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Other Observable Inputs (Level 2) | Cash and cash equivalents — money markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Other Observable Inputs (Level 2) | Equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Other Observable Inputs (Level 2) | Equity funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Other Observable Inputs (Level 2) | Fixed income funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Unobservable Inputs (Level 3)      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Unobservable Inputs (Level 3) | Cash and cash equivalents — money markets      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Unobservable Inputs (Level 3) | Equities      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Unobservable Inputs (Level 3) | Equity funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets 0 0  
Significant Unobservable Inputs (Level 3) | Fixed income funds      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of plan assets $ 0 $ 0