Long-Term Debt And Notes Payable (Components Of Debt) (Detail 2)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2014	Mar. 31, 2015	Dec. 11, 2013
Two Point Seven Five Percent Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		2.75%	2.75%	2.75%
Debt instrument maturity year	2018	2018
Six Point Five Five Percent Notes Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		4.45%	4.45%
Debt instrument maturity year	2023	2023
Six Point Five Five Percent Notes Due 2036
Debt Instrument [Line Items]
Debt instrument interest rate		6.55%	6.55%
Debt instrument maturity year	2036	2036