Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 326,836	$ 218,403	$ 237,135	$ 76,970
Accounts receivable	441,185	551,269
Accounts receivable - affiliate	2,922	3,223
Inventories	1,129,207	1,102,261
Prepaid expense and other current assets	38,242	32,157
Total current assets	1,938,392	1,907,313
Property, plant and equipment, net	1,800,833	1,806,060
Deferred charges and other assets, net	328,548	330,517
Total assets	4,067,773	4,043,890
Current liabilities:
Accounts payable	312,988	335,182
Accounts payable - affiliate	13,950	11,630
Accrued expenses	998,823	1,129,970
Deferred revenue	6,086	1,227
Total current liabilities	1,331,847	1,478,009
Delaware Economic Development Authority loan	8,000	8,000
Long-term debt	741,233	742,349
Intercompany notes payable	153,023	122,264
Other long-term liabilities	67,413	62,752
Total liabilities	2,301,516	2,413,374
Commitments and contingencies (Note 8)
Equity:
Member's equity	1,144,114	1,144,100
Retained earnings	648,548	513,292
Accumulated other comprehensive loss	(26,405)	(26,876)
Total equity	1,766,257	1,630,516
Total liabilities and equity	$ 4,067,773	$ 4,043,890