Revenue from Contracts with Customers (ASC 606) Financial Statement Impact of Adopting ASC 606 (Details) - USD ($)	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Financial Statement Impact of Adopting ASC 606 [Line Items]
Cash, Cash Equivalents, and Short-term Investments	$ 33,236,000		$ 42,915,000
Accounts receivable, net of allowance for doubtful accounts of $2,786 and $2,852 as of September 30, 2018 and December 31, 2017, respectively	28,971,000		28,316,000
Inventories	24,676,000		22,732,000
Current contract assets	3,460,000	$ 3,205,000	0
Prepaid Expense and Other Assets	3,741,000		3,816,000
Long-Lived Assets	96,860,000		92,513,000
Other Assets, Noncurrent	6,701,000		5,927,000
Non-current contract assets	6,626,000	5,963,000	0
Non-current deferred income tax asset	201,000		20,000
Assets	204,472,000		196,239,000
Accounts Payable and Other Accrued Liabilities, Current	58,342,000		36,430,000
Deferred Revenue, Current	0		6,919,000
Contract liabilities	10,770,000	11,039,000	0
Long-term contract liabilities	8,771,000	7,998,000	0
Other Liabilities, Noncurrent			2,653,000
Long-term Debt, Excluding Current Maturities	20,252,000		44,572,000
Liabilities	102,742,000		90,574,000
Retained Earnings (Accumulated Deficit)	13,575,000		4,417,000
Common stock, additional paid-in capital, and accumulated other comprehensive loss	115,305,000		110,082,000
Stockholders' Equity Attributable to Parent	101,730,000		105,665,000
Liabilities and Equity	204,472,000		196,239,000
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Financial Statement Impact of Adopting ASC 606 [Line Items]
Cash, Cash Equivalents, and Short-term Investments		42,915,000
Accounts receivable, net of allowance for doubtful accounts of $2,786 and $2,852 as of September 30, 2018 and December 31, 2017, respectively		28,316,000
Inventories		22,732,000
Current contract assets		3,205,000
Prepaid Expense and Other Assets		3,816,000
Long-Lived Assets		92,513,000
Other Assets, Noncurrent		5,927,000
Non-current contract assets		5,963,000
Non-current deferred income tax asset		222,000
Assets		205,609,000
Accounts Payable and Other Accrued Liabilities, Current		36,430,000
Deferred Revenue, Current		0
Contract liabilities		11,039,000
Long-term contract liabilities		7,998,000
Other Liabilities, Noncurrent		2,653,000
Long-term Debt, Excluding Current Maturities		44,572,000
Liabilities		102,692,000
Retained Earnings (Accumulated Deficit)		7,165,000
Common stock, additional paid-in capital, and accumulated other comprehensive loss		110,082,000
Stockholders' Equity Attributable to Parent		102,917,000
Liabilities and Equity		$ 205,609,000
Accounting Standards Update 2014-09 [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Financial Statement Impact of Adopting ASC 606 [Line Items]
Cash, Cash Equivalents, and Short-term Investments	33,236,000
Accounts receivable, net of allowance for doubtful accounts of $2,786 and $2,852 as of September 30, 2018 and December 31, 2017, respectively	28,971,000
Inventories	24,676,000
Current contract assets	0
Prepaid Expense and Other Assets	3,741,000
Long-Lived Assets	96,860,000
Other Assets, Noncurrent	6,701,000
Non-current contract assets	0
Non-current deferred income tax asset	46,000
Assets	194,231,000
Accounts Payable and Other Accrued Liabilities, Current	58,342,000
Deferred Revenue, Current	6,424,000
Contract liabilities	0
Long-term contract liabilities	0
Long-term Debt, Excluding Current Maturities	20,252,000
Liabilities	89,625,000
Retained Earnings (Accumulated Deficit)	10,699,000
Common stock, additional paid-in capital, and accumulated other comprehensive loss	115,305,000
Stockholders' Equity Attributable to Parent	104,606,000
Liabilities and Equity	194,231,000
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Financial Statement Impact of Adopting ASC 606 [Line Items]
Cash, Cash Equivalents, and Short-term Investments			0
Accounts receivable, net of allowance for doubtful accounts of $2,786 and $2,852 as of September 30, 2018 and December 31, 2017, respectively			0
Inventories			0
Current contract assets			3,205,000
Prepaid Expense and Other Assets			0
Long-Lived Assets			0
Other Assets, Noncurrent			0
Non-current contract assets			5,963,000
Non-current deferred income tax asset			202,000
Assets	10,241,000		9,370,000
Accounts Payable and Other Accrued Liabilities, Current			0
Deferred Revenue, Current			(6,919,000)
Contract liabilities			11,039,000
Long-term contract liabilities			7,998,000
Other Liabilities, Noncurrent			0
Long-term Debt, Excluding Current Maturities			0
Liabilities	$ 13,117,000		12,118,000
Retained Earnings (Accumulated Deficit)			2,748,000
Common stock, additional paid-in capital, and accumulated other comprehensive loss			0
Stockholders' Equity Attributable to Parent			(2,748,000)
Liabilities and Equity			9,370,000
Deferred Revenue			12,118,000
Contract with Customer, Asset, Net			9,370,000
Sales Commission [Member] | Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Financial Statement Impact of Adopting ASC 606 [Line Items]
Retained Earnings (Accumulated Deficit)			(191,000)
Deferred Tax Assets, Net			$ 203,000