Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of total capital expenditures incurred to total capital expenditures in the consolidated statements of cash flows
Capital expenditures incurred	$ 352,055	$ 140,153
Additions incurred prior year but paid for in current year	123,548	29,264
Additions incurred but not paid for as of the end of the year	106,574	28,774
Capital expenditures per Consolidated Statements of Cash Flows	$ 369,029	$ 140,643