Long-Term Borrowings - Future Contractual Principal Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Future contractual principal payments on long term borrowings
2019	$ 9
2020	200,009
2021	10
2023	100,000
Thereafter	100,000
Total	400,028	$ 600,026
FHLB fixed-rate advance
Future contractual principal payments on long term borrowings
Total	$ 400,000	$ 600,000
FHLB fixed-rate advance \| December 4, 2020
Future contractual principal payments on long term borrowings
Interest rate (as a percent)	2.80%
FHLB fixed-rate advance \| January 15, 2021
Future contractual principal payments on long term borrowings
Interest rate (as a percent)	2.65%

Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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