Employee Benefit Plan - Narrative (Details) - USD ($) |
6 Months Ended | |
|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Retirement Benefits [Abstract] | ||
| Amortization of amounts previously recognized in accumulated other comprehensive income | $ 625,000 | $ 655,000 |
| Contribution to pension plan | $ 0 | $ 0 |