Deposits - Total Deposits by Category (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deposits, by Component [Abstract]
Noninterest-bearing demand deposits	$ 1,125,598	$ 964,900
Demand and money market	1,498,707	1,214,382
Savings deposits	318,749	399,754
Time deposits	860,613	923,565
Brokered time deposits	63,533	127,993
Total deposits	$ 3,867,200	$ 3,630,594
Percentage of Noninterest and Interest Bearing Domestic Deposit Liabilities [Abstract]
Noninterest-bearing demand deposits	29.10%	26.60%
Interest-bearing deposits:
Demand and money market	38.80%	33.50%
Savings deposits	8.20%	11.00%
Time deposits	22.30%	25.40%
Brokered time deposits	1.60%	3.50%
Total deposits	100.00%	100.00%

Brokered deposits.

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Demand and money market

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Percentage of Interest and Noninterest Bearing Domestic Deposits to Deposits

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Percentage of Interest Bearing Domestic Deposits To Deposits, Demand and Money Market

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Percentage of Noninterest and Interest Bearing Domestic Deposit Liabilities [Abstract]

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Percentage of Noninterest Bearing Domestic Deposits to Deposits

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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Percentage of interest-bearing domestic brokered deposit liabilities to total deposit liabilities.

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Percentage of interest-bearing domestic time deposit liabilities other than certificates of deposit liabilities to total deposit liabilities.

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Percentage of interest-bearing domestic savings deposit liabilities to total deposit liabilities.

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Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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