Borrowings - Contractual Maturities Repurchase Agreements And FHLB Advances (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long Term Debt Maturities Repayments Of Principal [Line Items]
Total long term debt	$ 857,004	$ 408,891
FHLB Advances
Long Term Debt Maturities Repayments Of Principal [Line Items]
2019	411,000
2020	145,000
2021	95,000
2022	87,500
2023	25,000
Thereafter	12,500
Total long term debt	776,000
Repurchase agreements
Long Term Debt Maturities Repayments Of Principal [Line Items]
2019	0
2020	25,000
2021	25,000
2022	0
2023	25,000
Total long term debt	$ 75,000

Long Term Debt Maturities Repayments Of Principal [Line Items]

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Long-term Debt, Maturities, Repayments of Principal in Rolling Thereafter

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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