Operating Leases (Tables)

12 Months Ended

Dec. 31, 2017

Leases, Operating [Abstract]

Future Rental Commitments Over the Next Five Years Under Non-cancelable Operating Leases

A summary of future rental commitments over the next five years under non-cancelable operating leases follows (in thousands):

Years Ending December 31,
2018	$	10,334
2019	9,812
2020	9,480
2021	9,435
2022	9,251
Total	$	48,312