Fair Value of Financial Instruments (Details) - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Liabilities
Derivative Liability	$ 4,106,000		$ 3,608,000
Recurring Basis
Assets
Money market funds	81,822,000		98,789,000
Derivative financial instruments	7,258,000		17,111,000
Liabilities
Derivative Liability	4,106,000		3,608,000
Transfer of assets from level 1 to level 2	0		0
Transfer of assets from level 2 to level 1	0		0
Transfer of liabilities from level 1 to level 2	0		0
Transfer of liabilities from level 2 to level 1	0		0
Transfer of assets into level 3	0	$ 0
Transfer of assets out of level 3	0	0
Transfer of liabilities into level 3	0	0
Transfer of liabilities out of level 3	0	$ 0
Recurring Basis | Level 1
Assets
Money market funds	81,822,000		98,789,000
Derivative financial instruments	0		0
Demand deposits	41,700,000		70,000,000
Liabilities
Derivative Liability	0		0
Recurring Basis | Level 2
Assets
Money market funds	0		0
Derivative financial instruments	7,258,000		17,111,000
Liabilities
Derivative Liability	$ 4,106,000		$ 3,608,000