Summary of Significant Accounting Policies - Operating and Capital Leases (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Future Cash Payments, Capital Lease:
2019	$ 521
2020	474
2021	243
2022	256
2023	71
Total	1,565
Future Cash Payments, Operating Leases:
2019	2,927
2020	2,771
2021	2,512
2022	1,243
2023	971
Thereafter	652
Total	$ 11,076