Revolving Credit Facility and Bank Borrowings (Revolving Credit Facilities and Notes Payable) (Details)	Oct. 13, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2017 CNY (¥)	Dec. 31, 2016 USD ($)
Line of Credit Facility [Line Items]
Amount allowed for repurchase under Amendment		$ 91,700,000
Senior Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Outstanding letters of credit		1,300,000
Revolving Credit Facility [Member] | Senior Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Amount allowed for repurchase under Amendment		50,000,000
Maximum capital expenditures and commitments		50,000,000
Borrowings outstanding threshold for financial covenant ratios		$ 20,000,000
Minimum fixed charge coverage ratio		110.00%	110.00%
Leverage ratio		200.00%	200.00%
Outstanding borrowings on the Facility		$ 0
Available borrowing capacity		78,700,000		$ 78,700,000
Current borrowing capacity		80,000,000.0
Revolving Credit Facility [Member] | Asia Pacific Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Current borrowing capacity		9,000,000	¥ 60,000,000
Revolving Loan Facility [Member] | Asia Pacific Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Current borrowing capacity		$ 6,000,000	¥ 40,000,000
Subsequent Event [Member] | Revolving Credit Facility [Member] | Senior Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Borrowings outstanding threshold for financial covenant ratios	$ 40,000,000
Current borrowing capacity	$ 100,000,000
Percentage of commitments in average outstanding borrowings (percent)	40.00%
Intercompany loans permitted	$ 375,000,000