Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Detail)

v3.19.1
Summary of Significant Accounting Policies - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Detail)
$ in Thousands
Dec. 31, 2018
USD ($)
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 12,916
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 11,537
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 606
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 331
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 179
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 94
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01  
Disaggregation of Revenue [Line Items]  
Revenue, Remaining Performance Obligation $ 169
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction