CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
REVENUES:
Contract drilling	$ 1,342,052	$ 1,103,397	$ 1,017,923
Revenues related to reimbursable expenses	53,799	70,556	45,740
Total revenues	1,395,851	1,173,953	1,063,663
COSTS AND EXPENSES:
Contract drilling	520,421	506,128	426,198
Reimbursable expenses	38,744	56,225	32,727
Depreciation	171,947	147,358	117,510
General and administrative	57,229	61,461	56,786
Asset impairment	60,777	0	0
(Gain) loss on sale of assets	15,303	(34,139)	971
Other, net	0	(1,864)	0
Total costs and expenses	864,421	735,169	634,192
OPERATING INCOME	531,430	438,784	429,471
OTHER INCOME (EXPENSE):
Interest expense, net of capitalized interest	(52,551)	(41,803)	(24,903)
Interest income	91	312	233
Other income (expense) total	(52,460)	(41,491)	(24,670)
INCOME BEFORE INCOME TAXES	478,970	397,293	404,801
PROVISION FOR INCOME TAXES	46,397	56,471	54,577
NET INCOME	$ 432,573	$ 340,822	$ 350,224
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 6.70	$ 5.31	$ 5.38
Diluted (in dollars per share)	$ 6.65	$ 5.24	$ 5.32
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING (NOTE 2):
Basic (in shares)	64,581	64,240	65,073
Diluted (in shares)	65,030	65,074	65,845