Transfers of Financial Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Transfers and Servicing of Financial Assets [Abstract]
Purchase of Euro-denominated loans		$ 27,400
Loans sold and derecognized	$ 27,400
Transfers of financial assets accounted for as sale, initial fair value of assets obtained as proceeds	21,500
Trades receivable for loans subject to forward sale agreement	0	10,391
Loans held for sale	0	8,204
Obligation to deliver loans subject to forward sale agreement, at fair value	$ 0	$ 8,204

The amount owed to the reporting entity by counterparties in securitized loan transactions.

No definition available.

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- Definition

The aggregate cash outflow used to purchase all loans that are held with the intention to resell in the near future.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 55
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=34726456&loc=d3e60097-112785

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3367-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3461-108585

+ Details

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3337-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3461-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 55
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=34726456&loc=d3e60097-112785

+ Details

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- Definition

Amount, after allowance for bad debt, of trade and loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

+ Details

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- Definition

The carrying amount of liabilities as of the balance sheet date that pertain to principal and customer trading transactions, or which may be incurred with the objective of generating a profit from short-term fluctuations in price as part of an entity's market-making, hedging and proprietary trading. Examples include short positions in securities, derivatives and commodities, obligations under repurchase agreements, and securities borrowed arrangements.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Represents the initial fair value recorded for assets received on transfer of financial assets in a securitization, asset-backed financing arrangement, or a similar transfer which transaction is recognized as a sale of the transferred financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)(2)(i)
-URI http://asc.fasb.org/extlink&oid=64830801&loc=d3e107207-111719

+ Details

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