Income Tax Matters Income Tax Matters Narrative (Details)					12 Months Ended
		May 26, 2016 $ / shares	Apr. 22, 2016	Apr. 07, 2016	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2013 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption	[1]					$ 700,000
Operating Loss Carryforwards					$ 414,100,000
Tax Credit Carryforward, Amount					26,800,000
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount					(5,500,000)	2,000,000	$ (700,000)
Unrecognized Tax Benefits					1,800,000	1,700,000	2,200,000		$ 3,800,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate					700,000	600,000	1,100,000
Accrued interest and penalties on unrecognized tax benefits					200,000	200,000
Accrued interest and penalties on unrecognized tax benefits, current					$ 0
(Decrease) increase in interest and penalty						(1,200,000)	(900,000)
Foreign currency impact on gross unrecognized tax benefit (including interest and penalties) which increased (decreased) Other comprehensive income (loss)						$ 100,000	$ 300,000
New Accounting Pronouncement, Early Adoption, Effect [Member] | Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption								$ 700,000
Series A Preferred Stock [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Preferred Stock, Rights Conversion Ratio into Preferred Stock				1
Preferred Stock, Redemption Price Per Share | $ / shares		$ 400
Preferred Stock, Rights Waiting Period, Duration Before Exercisable After Public Announcement		10 days
Preferred Stock, Rights Waiting Period, Duration Before Exercisable After Tender or Exchange Offer Results in Becoming an Acquiring Person		10 days
Value of right to purchase shares of the acquiring or other appropriate entity			2

[1] See Note 5 and Note 8 for discussion of our adoption of ASU 2016-09 (as defined in Note 1).