Organization and Summary of Significant Accounting Policies (Fair Value on a Nonrecurring Basis) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets at fair value and gains (losses) recorded
Derivative, Notional Amount	$ 100,000,000
Derivatives		$ 0
Equipment held for sale	30,710,000	23,454,000
Assets at fair value	69,000
Increase (decrease) in asset write-down	25,000
Asset write-down	9,514,000	9,181,000	$ 5,602,000
Additional write-down		2,800,000
Asset helf-for-use write-down		300,000
Equipment
Assets at fair value and gains (losses) recorded
Asset helf-for-use write-down		600,000
Engine Parts
Assets at fair value and gains (losses) recorded
Asset write-down	2,000,000
Additional write-down	2,000,000
Recurring | Level 1
Assets at fair value and gains (losses) recorded
Derivatives	69,000
Total	69,000
Recurring | Level 3
Assets at fair value and gains (losses) recorded
Derivatives	69,000
Total	69,000
Nonrecurring
Assets at fair value and gains (losses) recorded
Equipment held for lease	1,196,000	2,154,000
Equipment held for sale	8,976,000	4,931,000
Spare parts inventory	1,538,000
Assets at fair value	11,710,000	7,085,000
Total losses on equipment held for lease	(3,674,000)	(2,536,000)
Total losses on equipment held for sale	(5,365,000)	(6,645,000)
Total losses on spare parts inventory	(475,000)
Total losses on assets	(9,514,000)	(9,181,000)
Nonrecurring | Equipment
Assets at fair value and gains (losses) recorded
Asset write-down recorded earlier	5,500,000
Nonrecurring | Level 2
Assets at fair value and gains (losses) recorded
Equipment held for lease	1,196,000	2,154,000
Equipment held for sale	8,976,000	4,931,000
Spare parts inventory	1,538,000
Assets at fair value	11,710,000	$ 7,085,000
Engines and related equipment | Nonrecurring
Assets at fair value and gains (losses) recorded
Asset write-down	$ 9,500,000