Financing Agreements Redemption Price Expressed as Percentage of Principal Amount Senior Notes Sold in 2013 (Detail)	Dec. 31, 2013
Senior Notes Due September 2021 [Member] | 2016
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	104.031%
Senior Notes Due September 2021 [Member] | 2017
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	102.688%
Senior Notes Due September 2021 [Member] | 2018
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	101.344%
Senior Notes Due September 2021 [Member] | 2019
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	100.00%
Senior Notes Due September 2021 [Member] | 2020
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	100.00%
Senior Notes Due September 2023 [Member] | 2018
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	103.00%
Senior Notes Due September 2023 [Member] | 2019
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	102.00%
Senior Notes Due September 2023 [Member] | 2020
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	101.00%
Senior Notes Due September 2023 [Member] | 2021
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	100.00%
Senior Notes Due September 2023 [Member] | 2022
Extinguishment of Debt [Line Items]
Debt Redemption Price Expressed as Percent of Principal Amount	100.00%