Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended		3 Months Ended		9 Months Ended
	Apr. 30, 2014	Apr. 29, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Apr. 30, 2014 entity	Dec. 31, 2013
Accounting Policies [Abstract]
Number of legally separate publicly traded entities							2
Number of shares issued for each share prior to spin-off							1
Beginning Equity balance post-Spin-Off							$ 1,710,000,000
Preferred stock value outstanding							565,000,000
Special cash contribution from Spin Off					472,718,000	0
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum days past due that company may required spin-off company to purchase loans					90 days
Period of hardship forbearance					6 months
Split loans held			7,779,422,000		7,779,422,000			6,506,642,000
Loss confirmation period	1 year	2 years
Amount of change in allowance due to policy change					14,000,000
Loans sold			1,200,000,000	600,000,000	1,900,000,000	2,300,000,000
Gains on sales of loans, net			85,147,000	43,434,000	120,963,000	192,097,000
Deferred taxes payable			283,118,000		283,118,000		283,000,000	162,205,000
Indemnification receivable							264,000,000
Liability for uncertain tax positions, current			16,000,000		16,000,000		27,000,000
Deferred tax and uncertain tax positions liability			299,000,000		299,000,000		310,000,000
Deferred tax liability			283,000,000		283,000,000		283,000,000
Tax indemnification receivable			253,681,000		253,681,000		291,000,000	0
Deferred tax assets			238,000,000		238,000,000		310,000,000
Deferred tax asset discount			16,000,000		16,000,000		19,000,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan delinquency period	30 days	150 days
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan delinquency period	120 days	212 days
Split Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Split loans held			$ 126,000,000		$ 126,000,000