Debt - Additional Information (Detail) (USD $)	9 Months Ended
Sep. 30, 2014
Debt Disclosure [Abstract]
Senior notes principal amount	$ 600,000,000
Senior notes effective interest rate	3.97%
Senior notes maturity	Sep. 15, 2022
Senior notes interest rate	3.95%
Frequency of senior notes payment	Semi-annually in arrears on March 15 and September 15.
Repurchase agreement maximum loan borrowing capacity	25,000,000
Borrowing base	0
Debt outstanding under repurchase agreement	$ 0
Expiration date of repurchase agreement	Jul. 29, 2015

Debt instrument borrowing base limitation amount.

No definition available.

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- Definition

Expiration date of repurchase agreement.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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- Definition

Carrying value as of the balance sheet date of the outstanding short-term borrowings under a revolving line of credit used by mortgage bankers to finance the origination or purchase of loans.

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