Commitments And Contingencies (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($) item		Dec. 31, 2014 USD ($)
Commitments And Contingencies [Abstract]
Lease term	5 years
Office facility expense	$ 1,700	$ 1,500		$ 1,500
Number of outstanding letters of credit | item	1	1
Outstanding letter of credit	$ 100	$ 100
Rental equipment payable	25,207	$ 10,901	[1]
Commitments to purchase rental equipment	189,500
Commitments to purchase rental equipment, year one	117,400
Commitments to purchase rental equipment, year two	$ 72,100

[1] Amounts for the year ended December 31, 2015 have been restated for immaterial corrections of identified errors relating to prepaid loan fees (see Note 2 (b) "Correction of Immaterial Errors").