Investment Securities - Additional Information (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) security	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) security	Sep. 30, 2015 USD ($)	Dec. 31, 2015 security
Investments Debt And Equity Securities [Abstract]
Number of securities in securities portfolio \| security	302		302		274
Number of securities in securities portfolio, unrealized loss position \| security	19		19		64
Other-than-temporary impairment recorded by the company \| $	$ 0	$ 0	$ 0	$ 0
Trade date receivable related to securitization of mortgage loans held for sale \| $	$ 32,648,000		$ 32,648,000

Number of available for sale securities in portfolio.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

+ Details

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- References

No definition available.

+ Details

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284393-111563

+ Details

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