Income Taxes Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net	$ 2,233	$ 481	$ (429)
Available-for-sale Securities, Income Tax Expense on Change in Unrealized Holding Gain (Loss)	21	$ 5	$ 16
US Federal [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 15,300
Operating Loss Expiration Date, Range Start	2021
State and Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 50
Tax Credit Carryforward, Amount	$ 2,300
Operating Loss Expiration Date, Range Start	2017