Consolidated Condensed Statements of Earnings (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Lease and rental revenues	$ 798,387	$ 779,046	$ 1,566,141	$ 1,508,070
Services revenue	785,791	737,170	1,544,918	1,430,874
Fuel services revenue	119,566	146,715	222,357	291,140
Total revenues	1,703,744	1,662,931	3,333,416	3,230,084
Cost of lease and rental	555,302	531,308	1,107,792	1,049,730
Cost of services	646,129	603,488	1,277,843	1,185,818
Cost of fuel services	115,478	142,176	214,379	278,465
Other operating expenses	27,796	29,582	57,947	61,955
Selling, general and administrative expenses	222,448	214,868	433,661	421,473
Gains on used vehicles, net	(12,000)	(29,985)	(31,129)	(57,193)
Interest expense	37,268	39,075	75,157	75,877
Miscellaneous income, net	(5,456)	(1,028)	(7,721)	(3,665)
Total expenses	1,586,965	1,529,484	3,127,929	3,012,460
Earnings from continuing operations before income taxes	116,779	133,447	205,487	217,624
Provision for income taxes	42,737	47,530	75,260	78,381
Earnings from continuing operations	74,042	85,917	130,227	139,243
Loss from discontinued operations, net of tax	(292)	(758)	(683)	(1,295)
Net earnings	$ 73,750	$ 85,159	$ 129,544	$ 137,948
Earnings (loss) per common share — Basic
Continuing operations (in dollars per share)	$ 1.39	$ 1.62	$ 2.45	$ 2.63
Discontinued operations (in dollars per share)	(0.01)	(0.01)	(0.01)	(0.02)
Net earnings (in dollars per share)	1.39	1.61	2.43	2.61
Earnings (loss) per common share — Diluted
Continuing operations (in dollars per share)	1.38	1.61	2.43	2.61
Discontinued operations (in dollars per share)	(0.01)	(0.01)	(0.01)	(0.03)
Net earnings (in dollars per share)	1.38	1.59	2.42	2.59
Cash dividends declared per common share (in dollars per share)	$ 0.41	$ 0.37	$ 0.82	$ 0.74