Deposits (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Deposits [Abstract]
Noninterest bearing deposits		$ 803,316	$ 790,930
NOW accounts		56,964	51,218
Money market deposits		887,288	692,021
Savings		406,749	416,551
Certificates of deposit and other time deposits of $100,000 or more		651,967	759,025
Certificates of deposit and other time deposits less than $100,000		499,666	554,118
Total deposits		3,305,950	3,263,863
Certificates of deposit and other time deposits of $250,000 or more		219,000	232,500
Wholesale brokered deposits		42,300	$ 82,300
Wholesale brokered deposits matured during period	$ 40,000
Maturities of Time Deposits [Abstract]
Total		1,151,633
Within 1 Year		840,592
2 Years		168,637
3 Years		64,312
4 Years		41,716
5 Years		36,118
After 5 Years		258
Certificates of Deposit and Other Time Deposits of $100,000 or More [Member]
Maturities of Time Deposits [Abstract]
Total		651,967
Within 1 Year		438,837
2 Years		125,420
3 Years		40,706
4 Years		27,135
5 Years		19,869
After 5 Years		0
Certificates of Deposit and Other Time Deposits Less Than $100,000 [Member]
Maturities of Time Deposits [Abstract]
Total		499,666
Within 1 Year		401,755
2 Years		43,217
3 Years		23,606
4 Years		14,581
5 Years		16,249
After 5 Years		$ 258

Amount of noninterest-bearing domestic third-party brokered deposits, which matured during the period.

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The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $250,000 or more.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
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Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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Amount of deposits in interest-bearing transaction accounts at banks or savings and loans, that are restricted in regard to ownership and can usually only be held by individuals, nonprofit entities and governments. Negotiable order of withdrawal accounts differ from money market demand accounts as they typically have higher reserve requirements and no limit on the number of checks that can be written.

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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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Amount of noninterest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

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Amount of time deposits maturing after the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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Amount of time deposits maturing in the fifth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the fourth fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the next fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the third fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposits maturing in the second fiscal year following the latest fiscal year. Time deposits include, but are not limited to, certificates of deposits. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of time deposit liabilities, including certificates of deposit.

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-Publisher FASB
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-Topic 942
-SubTopic 405
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Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
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Amount of time deposit liabilities, including certificates of deposit, in denominations of less than $100,000.

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