Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive income (loss) (pretax):
Net earnings	$ 161,470	$ 136,333	$ 287,200	$ 242,978
Comprehensive income (loss) (tax effect):
Net earnings	(60,459)	(51,114)	(107,966)	(91,257)
Comprehensive income (loss) (net of tax):
Net earnings	101,011	85,219	179,234	151,721
Other comprehensive income (loss):
Foreign currency translation (pretax)	(6,749)	2,097	(5,757)	(1,779)
Foreign currency translation (tax effect)	0	0	0	0
Foreign currency translation (net of tax)	(6,749)	2,097	(5,757)	(1,779)
Unrealized gain (loss) on investments (pretax)	(1,373)	5,575	(6,751)	6,763
Unrealized gain (loss) on investments (tax effect)	741	(1,927)	2,742	(2,249)
Unrealized gain (loss) on investments (net of tax)	(632)	3,648	(4,009)	4,514
Change in fair value of cash flow hedges (pretax)	(12,250)	(7,485)	(16,110)	(19,568)
Change in fair value of cash flow hedges (tax effect)	4,655	2,844	6,122	7,436
Change in fair value of cash flow hedges (net of tax)	(7,595)	(4,641)	(9,988)	(12,132)
Total comprehensive income (loss) (pretax)	141,098	136,520	258,582	228,394
Total comprehensive income (loss) (tax effect)	(55,063)	(50,197)	(99,102)	(86,070)
Total comprehensive income (loss) (net of tax)	$ 86,035	$ 86,323	$ 159,480	$ 142,324