Gain on Sale/Purchase of Other Assets (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Gain on Sale/Purchase of Other Assets [Abstract]
Number of International Flag Pure Car Truck Carriers sold				2
Proceeds from sale of other assets		$ 73,900,000
Gain on sale of other assets	667,000	3,799,000	0	4,466,000	0
Repayments of debt from sale proceeds		$ 36,100,000