Income Taxes (Details 5) $ in Thousands	Dec. 31, 2016 USD ($)
United States federal [Member]
Summary of tax credit carryforwards
Tax credit carryforwards	$ 123,672	[1]
California State [Member]
Summary of tax credit carryforwards
Tax credit carryforwards	36,348
States other than California [Member]
Summary of tax credit carryforwards
Tax credit carryforwards	6,738
Foreign Jurisdiction [Member]
Summary of tax credit carryforwards
Tax credit carryforwards	$ 14,241

[1] Certain of Cadence’s foreign tax credits have yet to be realized and as a result do not yet have an expiration period.