Recently Issued Accounting Standards ASU 2016-01 Recognition and Measurement of Financial Assets and Financial Liabilities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Accumulated Net Investment Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	$ 40
Accumulated Gain (Loss), Financial Liability, Fair Value Option, Including Portion Attributable to Noncontrolling Interest [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prior Period Reclassification Adjustment	$ 40,455