Summary Consolidated Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Quarterly Summary of Income Statement Data [Abstract]
Revenues	$ 2,455,238	$ 1,913,353	$ 1,599,199	$ 1,175,468	$ 2,027,907	$ 1,502,909	$ 1,363,512	$ 920,730	$ 7,143,258	$ 5,815,058	$ 5,169,508
Gross Profit	524,487	403,734	301,042	240,988	452,075	326,881	286,071	187,728
Income before income taxes	396,473	253,097	152,748	131,598	301,747	203,574	199,209	109,781	933,916	814,311	589,027
Net income	$ 310,976	$ 193,258	$ 111,810	$ 132,107	$ 191,878	$ 148,563	$ 124,638	$ 70,416	$ 748,151	$ 535,495	$ 382,095
Earnings Per Share [Abstract]
Earnings Per Share, Basic	$ 2.10	$ 1.28	$ 0.73	$ 0.85	$ 1.20	$ 0.91	$ 0.76	$ 0.43	$ 4.92	$ 3.30	$ 2.27
Earnings Per Share, Diluted	$ 2.08	$ 1.26	$ 0.72	$ 0.83	$ 1.17	$ 0.87	$ 0.73	$ 0.42	$ 4.85	$ 3.17	$ 2.18
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Basic weighted-average shares	148,066	151,257	152,731	155,882	159,232	163,478	163,492	162,588	151,984	162,222	168,261
Weighted Average Number of Shares Outstanding, Diluted	149,603	153,173	155,129	158,897	164,565	171,562	171,403	170,417	154,201	169,487	175,973