Summary of Significant Accounting Policies (Details 2)	12 Months Ended
Dec. 31, 2017 USD ($)
Accounting Policies [Abstract]
Income tax expense related to one-time mandatory repatriation of undistributed foreign subsidiary E&P	$ 0

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense

No definition available.

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Balance Type:	debit
Period Type:	duration