Income Taxes	3 Months Ended
Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We provide for income taxes for each interim period based on the estimated annual effective tax rate for the year, adjusting for discrete items in the quarter in which they arise. The annual effective tax rate before discrete items was 37.0% and 38.6% for the three months ended March 31, 2016 and 2015, respectively. The 2016 annual effective tax rate differed from the statutory rate of 35% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction and the Federal Research & Development credit, which was permanently reinstated on December 18, 2015. The 2015 annual effective tax rate differed from the statutory rate of 35% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction. As of March 31, 2016 and December 31, 2015, the Company had gross unrecognized tax benefits of $9.9 million and $7.2 million, respectively. It is the Company’s policy to classify accrued interest and penalties as part of the unrecognized tax benefits, but to record interest and penalties in operating expense. As of March 31, 2016 and December 31, 2015, the amount of accrued interest and penalties was $1.0 million and $0.2 million, respectively. As of March 31, 2016, calendar years 2011 and thereafter are open and subject to potential examination in one or more jurisdictions. However, because all of the net operating loss and research credit carryforwards that may be used in future years are subject to adjustment, if and when utilized, our federal and California tax years remain open from 1996 and 1992, respectively. The Company is currently under examination by the Internal Revenue Service for the 2011 through 2013 tax years. Although the Company believes it has adequately provided for uncertain tax positions, the provisions on these positions may change as revised estimates are made or the underlying matters are settled or otherwise resolved. It is not possible at this time to reasonably estimate changes in the unrecognized tax benefits within the next twelve months.

Income Taxes

We provide for income taxes for each interim period based on the estimated annual effective tax rate for the year, adjusting for discrete items in the quarter in which they arise. The annual effective tax rate before discrete items was 37.0% and 38.6% for the three months ended March 31, 2016 and 2015, respectively. The 2016 annual effective tax rate differed from the statutory rate of 35% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction and the Federal Research & Development credit, which was permanently reinstated on December 18, 2015. The 2015 annual effective tax rate differed from the statutory rate of 35% primarily due to the unfavorable impact of state income taxes, non-deductible equity charges, and other non-deductible expenditures, which were partially offset by the domestic production activities deduction.

As of March 31, 2016 and December 31, 2015, the Company had gross unrecognized tax benefits of $9.9 million and $7.2 million, respectively. It is the Company’s policy to classify accrued interest and penalties as part of the unrecognized tax benefits, but to record interest and penalties in operating expense. As of March 31, 2016 and December 31, 2015, the amount of accrued interest and penalties was $1.0 million and $0.2 million, respectively.

As of March 31, 2016, calendar years 2011 and thereafter are open and subject to potential examination in one or more jurisdictions. However, because all of the net operating loss and research credit carryforwards that may be used in future years are subject to adjustment, if and when utilized, our federal and California tax years remain open from 1996 and 1992, respectively. The Company is currently under examination by the Internal Revenue Service for the 2011 through 2013 tax years.

Although the Company believes it has adequately provided for uncertain tax positions, the provisions on these positions may change as revised estimates are made or the underlying matters are settled or otherwise resolved. It is not possible at this time to reasonably estimate changes in the unrecognized tax benefits within the next twelve months.