Income Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Contingency [Line Items]
Income tax provision
Change in unrecognized tax benefits during the period
Accrual for uncertain tax positions
Minimum [Member]
Income Tax Contingency [Line Items]
Tax years open for examination	2014
Maximum [Member]
Income Tax Contingency [Line Items]
Tax years open for examination	2017