Recent Accounting Pronouncements - Impact of Adoption of ASC 842 (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 2,981
Total assets	217,710		$ 223,524
Accrued liabilities	9,432		15,371
Total current liabilities	23,188		28,709
Long-term portion of lease obligations	2,744
Total liabilities	26,256		28,992
Total liabilities and equity	217,710		223,524
Accounts Receivable, Net, Current	17,450		19,586
Lease liability	$ 3,036
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets			1,086
Total assets			1,086
Accrued liabilities			128
Total current liabilities			128
Long-term portion of lease obligations			958
Total liabilities			1,086
Total liabilities and equity			$ 1,086
Adjustment [Member] | ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		$ 1,086
Total assets		224,610
Accrued liabilities		15,499
Total current liabilities		28,837
Long-term portion of lease obligations		958
Total liabilities		30,078
Total liabilities and equity		224,610
Lease liability		$ 1,100