Commitments and Contingencies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leased Assets [Line Items]
Counsel Fees and Expenses	$ 450,000
Rental expense	$ 3,400,000	$ 2,300,000	$ 1,900,000
Minimum
Operating Leased Assets [Line Items]
Leases renewal option term	2 years
Maximum
Operating Leased Assets [Line Items]
Leases renewal option term	10 years