Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Gross	$ 58,316,000	$ 64,570,000
Deferred Tax Assets, Tax Credit Carryforwards	11,380,000	19,529,000
Foreign Tax Credit Carryforward Expire On 2022	300,000
Foreign Tax Credit Carryforward Expire On 2023	1,900,000
Deferred Tax, Operating Loss Carryforwards	5,023,000	4,310,000
Valuation Allowance	3,998,000	2,837,000
Unrecognized Tax Liability For Undistributed Foreign Earnings	6,800,000
Liability for uncertain tax positions	2,700,000	1,500,000
Liability for uncertain tax positions, short-term liabilities	1,200,000
Increase (Decrease) in Uncertain Tax Liability	1,300,000
Accrued Interest And Penalties Related To Continued Operations	100,000
Accrued Income Taxes Payable	600,000	600,000
Accrued Interest and Penalties for Discontinued Operations	400,000	500,000
Income Taxes Paid	14,100,000	10,100,000	$ 8,400,000
Continuing Operations
Operating Loss Carryforwards [Line Items]
Expected tax position to be resolved or settled	200,000
Discontinued Operations
Operating Loss Carryforwards [Line Items]
Expected tax position to be resolved or settled	1,000,000
Maximum
Operating Loss Carryforwards [Line Items]
Foreign Tax Credit Carryforward Expire On 2021	100,000
Income Tax Penalties and Interest Expense	100,000
State and Foreign
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	63,000,000	56,000,000
Deferred Tax, Operating Loss Carryforwards	5,000,000	4,300,000
Valuation Allowance	4,000,000	2,800,000
State
Operating Loss Carryforwards [Line Items]
Valuation Allowance Operating Loss Carryforwards Change In Amount	1,200,000	(800,000)
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Valuation Allowance Operating Loss Carryforwards Change In Amount	1,200,000	$ (800,000)
Foreign Income Tax Credit
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Tax Credit Carryforwards	2,300,000
Foreign Income Tax Credit | U.S
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Tax Credit Carryforwards	$ 2,200,000
Tax credit carryforward expiration period	10 years
Foreign Income Tax Credit | Foreign Tax Authority | United Kingdom
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Tax Credit Carryforwards	$ 100,000
Alternative Minimum Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 9,100,000