Short-term Borrowings and Long-term FHLB Advances - Rate and Maturity Information on Federal Home Loan Bank Advances and Other Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other long-term debt	$ 55,374	$ 139,140
Bullet Maturity \| Fixed Rate
Other long-term debt	$ 55,374	118,131
Bullet Maturity \| Fixed Rate \| Weighted Average
Interest rate	1.76%
Bullet Maturity \| Fixed Rate \| Minimum
Interest rate	1.40%
Bullet Maturity \| Fixed Rate \| Maximum
Interest rate	2.13%
Convertible-fixed
Other long-term debt	$ 0	$ 21,009

Amount of long-term debt classified as other.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Name:	us-gaap_OtherLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant