Revenue from Contracts with Customers Narrative (Details) - USD ($)		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative impact of new standard	[1]	$ 754,000
Customer Deposits		8,167,000	$ 8,945,000
Contract Liabilities		11,500,000	12,500,000
Performance obligation satisfied in previous period		30,800,000
Cash payments received from customers		29,000,000
Contract assets		0
Revenue		106,732,000	$ 114,905,000	$ 86,489,000
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue		754,000
Calculated under Revenue Guidance in Effect before Topic 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue		105,978,000
Calculated under Revenue Guidance in Effect before Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract Liabilities		(1,800,000)
Accumulated Deficit
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative impact of new standard	[1]	$ 754,000
Accumulated Deficit | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative impact of new standard					$ 800,000

[1] Effective January 1, 2018, we adopted Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers. See Note 2. Significant Accounting Policies and Note 3. Revenue from Contracts with Customers for more information.