Represents the amount reclassified from unrecognized tax benefits against deferred tax assets.

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Tax Credit Carryforward, Subject To Expiration, Amount

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Represents the amount of unrecognized tax benefits which pertained to uncertain tax positions taken in tax return and was included in long-term income taxes payable as of the balance date.

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Represents the amount of unrecognized tax benefits which pertained to uncertain tax positions taken in tax returns and was recorded as a reduction of long-term deferred tax assets as of the balance sheet date, prior to reduction for federal tax benefit.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes (Details 3) (USD $)	12 Months Ended
Income Taxes (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Operating loss carryforwards
Reclassification of Unrecognized Tax Benefit Amount				$ 4,700,000
Unrecognized tax benefits, reduction of long-term deferred tax assets, before federal tax benefit	17,800,000	12,600,000
Unrecognized tax benefits included in long-term income taxes payable	2,100,000	6,200,000
Portion of unrecognized tax benefits, which if recognized, would be recorded as an income tax benefit	2,100,000	1,600,000
Amount of potential unrecognized tax benefit	900,000
Reconciliation of the beginning and ending amounts of unrecognized income tax benefits
Balance at the beginning of the period	18,794,000us-gaap_UnrecognizedTaxBenefits	16,773,000us-gaap_UnrecognizedTaxBenefits	16,610,000us-gaap_UnrecognizedTaxBenefits
Tax positions related to current year:
Additions	1,134,000	1,156,000	589,000
Tax positions related to prior years:
Additions	531,000	956,000	1,521,000
Reductions	(556,000)	(91,000)	(1,947,000)
Balance at the end of the period	19,903,000us-gaap_UnrecognizedTaxBenefits	18,794,000us-gaap_UnrecognizedTaxBenefits	16,773,000us-gaap_UnrecognizedTaxBenefits
Undistributed earnings	4,200,000
Alternative Minimum Tax Credits
Operating loss carryforwards
Tax credit carryforwards	2,500,000
Foreign Tax Credit
Operating loss carryforwards
Tax credit carryforwards	120,700,000
Federal
Operating loss carryforwards
Tax credit carryforwards subject to expiration	55,000,000
Federal \| Research and Development as label
Operating loss carryforwards
Tax credit carryforwards	32,700,000
Federal \| Excess Tax Benefits From Stock Option Tax Deductions
Operating loss carryforwards
Tax credit carryforwards	36,300,000
State
Operating loss carryforwards
Operating Loss Carryforwards	294,500,000
State \| Research and Development as label
Operating loss carryforwards
Tax credit carryforwards	18,600,000
State \| Excess Tax Benefits From Stock Option Tax Deductions
Operating loss carryforwards
Operating Loss Carryforwards	$ 97,500,000