Revenue from Contracts with Customers - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Customer deposits	$ 6,756,000		$ 8,945,000
Contract liabilities	(13,500,000)		$ (12,500,000)
Performance obligation satisfied in previous period	7,100,000
Cash payments received form customers	5,300,000
Contract assets	0
Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue recognized during period of adoption	(200,000)
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	1,300,000
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]
Contract liabilities	$ (800,000)
Retained Earnings | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 800,000