Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator for basic and diluted net income per share attributable to the Company's stockholders:
Net income attributable to the Company	$ 16us-gaap_NetIncomeLoss	$ 32us-gaap_NetIncomeLoss	$ 27us-gaap_NetIncomeLoss	$ 41us-gaap_NetIncomeLoss	$ 34us-gaap_NetIncomeLoss	$ 39us-gaap_NetIncomeLoss	$ 33us-gaap_NetIncomeLoss	$ 41us-gaap_NetIncomeLoss	$ 116us-gaap_NetIncomeLoss	$ 147us-gaap_NetIncomeLoss	$ 108us-gaap_NetIncomeLoss
Less: net income attributable to nonvested shares									(1)
Net income attributable to the Company's stockholders									$ 115	$ 147	$ 108
Denominator for basic net income per share attributable to the Company's stockholders:
Weighted average common shares outstanding	107,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,058,843	107,053,031	107,053,031
Effect of dilutive securities:
Dilutive effect of stock based compensation									497,301	415,837	415,837
Denominator for diluted net income per share attributable to the Company's stockholders:	108,000,000	108,000,000	108,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,000,000	107,556,144	107,468,868	107,468,868
Basic	$ 0.15us-gaap_EarningsPerShareBasic	$ 0.30us-gaap_EarningsPerShareBasic	$ 0.25us-gaap_EarningsPerShareBasic	$ 0.38us-gaap_EarningsPerShareBasic	$ 0.32us-gaap_EarningsPerShareBasic	$ 0.37us-gaap_EarningsPerShareBasic	$ 0.31us-gaap_EarningsPerShareBasic	$ 0.37us-gaap_EarningsPerShareBasic	$ 1.07us-gaap_EarningsPerShareBasic	$ 1.37us-gaap_EarningsPerShareBasic	$ 1.01us-gaap_EarningsPerShareBasic
Diluted	$ 0.14us-gaap_EarningsPerShareDiluted	$ 0.30us-gaap_EarningsPerShareDiluted	$ 0.25us-gaap_EarningsPerShareDiluted	$ 0.38us-gaap_EarningsPerShareDiluted	$ 0.32us-gaap_EarningsPerShareDiluted	$ 0.36us-gaap_EarningsPerShareDiluted	$ 0.31us-gaap_EarningsPerShareDiluted	$ 0.37us-gaap_EarningsPerShareDiluted	$ 1.06us-gaap_EarningsPerShareDiluted	$ 1.37us-gaap_EarningsPerShareDiluted	$ 1.00us-gaap_EarningsPerShareDiluted

Net Income Attributable To Shareholders

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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