Revolving Credit Facilities - Narrative (Details)				12 Months Ended
	Jul. 16, 2019 USD ($)	Feb. 22, 2016 USD ($)	Aug. 02, 2010 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Revolving Credit Facility | China
Line of Credit Facility [Line Items]
Revolving commitment amount	$ 1,000,000	$ 5,000,000
Unused capacity				$ 500,000
Revolving Credit Facility | Base Rate | China
Line of Credit Facility [Line Items]
Basis spread on variable rate		110.00%
Revolving Credit Facility | Credit Agreement Due 2019
Line of Credit Facility [Line Items]
Revolving commitment amount			$ 175,000,000.0
Revolving Credit Facility | Credit Agreement Due 2020
Line of Credit Facility [Line Items]
Revolving commitment amount			160,000,000.0
Revolving Credit Facility | Credit Agreement
Line of Credit Facility [Line Items]
Increased current borrowing capacity			$ 50,000,000.0
Ratio of indebtedness to net capital						3.00	3.50
Maximum leverage ratio					3.00	4.75	4.50
Conversion ratio						5.00	5.00
Minimum leverage ratio					5.00	3.50	4.00
Revolving Credit Facility | ABL Credit Agreement
Line of Credit Facility [Line Items]
Revolving commitment amount	105,000,000
Write off of deferred debt issuance cost	100,000
Additional increase to borrowing capacity	20,000,000
ABL Credit Facility outstanding				60,727,000
Letters of credit outstanding				1,700,000
Unamortized discount and deferred financing costs	300,000
Deferred financing costs	1,700,000
Amortization of deferred financing costs	200,000
Interest expense				100,000
Revolving Credit Facility | ABL Credit Agreement | US
Line of Credit Facility [Line Items]
ABL Credit Facility outstanding				60,100,000
Revolving Credit Facility | ABL Credit Agreement | UK
Line of Credit Facility [Line Items]
Revolving commitment amount	15,000,000
ABL Credit Facility outstanding				$ 600,000
Bridge Loan | ABL Credit Agreement
Line of Credit Facility [Line Items]
Revolving commitment amount	10,500,000
Letter of Credit | ABL Credit Agreement
Line of Credit Facility [Line Items]
Revolving commitment amount	$ 10,000,000
Minimum | Revolving Credit Facility | Credit Agreement | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate			0.50%
Minimum | Revolving Credit Facility | Credit Agreement | Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate			1.50%
Minimum | Revolving Credit Facility | ABL Credit Agreement | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Minimum | Revolving Credit Facility | ABL Credit Agreement | Base Rate | US
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Minimum | Revolving Credit Facility | ABL Credit Agreement | Base Rate | UK
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Maximum | Revolving Credit Facility | Credit Agreement | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate			2.25%
Maximum | Revolving Credit Facility | Credit Agreement | Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate			3.25%
Maximum | Revolving Credit Facility | ABL Credit Agreement | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.50%
Maximum | Revolving Credit Facility | ABL Credit Agreement | Base Rate | US
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.50%
Maximum | Revolving Credit Facility | ABL Credit Agreement | Base Rate | UK
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.50%