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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Weighted average interest rate of debt outstanding.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Borrowings (Schedule of Other Borrowings) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Aug. 31, 2016	Dec. 31, 2015
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 597,847		$ 242,391
Long-term borrowings, Weighted Average Rate	1.63%		1.61%
Total short-term and long-term borrowings	$ 1,422,847		$ 342,391
Total short-term and long-term borrowings, Weighted Average Rate	1.06%		1.24%
FHLB advances: 0.60% - 0.66% fixed-rate notes \| Minimum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	0.60%
FHLB advances: 0.60% - 0.66% fixed-rate notes \| Maximum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	0.66%
Federal Home Loan Bank Advances \| FHLB advances: 0.81% - 7.44% fixed-rate notes due 2017 to 2020
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 438,538		$ 181,394
Long-term borrowings, Weighted Average Rate	1.24%		1.41%
Advances payable from Federal Home Loan Banks	$ 437,800		$ 181,000
Purchase accounting premiums	$ 700		400
Federal Home Loan Bank Advances \| FHLB advances: 0.81% - 7.44% fixed-rate notes due 2017 to 2020 \| Minimum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	0.81%
Federal Home Loan Bank Advances \| FHLB advances: 0.81% - 7.44% fixed-rate notes due 2017 to 2020 \| Maximum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	7.44%
Securities sold under agreements to repurchase \| Securities sold under agreements to repurchase: 1.48% - 4.11% fixed-rate notes due through 2017
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 19,144		$ 17,453
Long-term borrowings, Weighted Average Rate	3.17%		0.27%
Advances payable from Federal Home Loan Banks	$ 19,000		$ 17,000
Purchase accounting premiums	$ 100		500
Securities sold under agreements to repurchase \| Securities sold under agreements to repurchase: 1.48% - 4.11% fixed-rate notes due through 2017 \| Minimum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	1.48%
Securities sold under agreements to repurchase \| Securities sold under agreements to repurchase: 1.48% - 4.11% fixed-rate notes due through 2017 \| Maximum
Short Term Borrowings and Long Term Debt [Line Items]
Stated interest rate	4.11%
Line of Credit
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 124,625	$ 125,000	$ 25,000
Long-term borrowings, Weighted Average Rate	2.52%		2.27%
Line of Credit \| LIBOR
Short Term Borrowings and Long Term Debt [Line Items]
Basis spread on variable rate	1.75%
Subordinated Debt Obligations
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 0		$ 18,544
Long-term borrowings, Weighted Average Rate	0.00%		3.99%
Subordinated Debt Obligations \| Subordinated debt obligations: floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 11,285		$ 0
Long-term borrowings, Weighted Average Rate	3.14%		0.00%
Purchase accounting discounts	$ 3,700
Advances payable	$ 15,000
Subordinated Debt Obligations \| Subordinated debt obligations: floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 \| Minimum \| LIBOR
Short Term Borrowings and Long Term Debt [Line Items]
Basis spread on variable rate	1.45%
Subordinated Debt Obligations \| Subordinated debt obligations: floating-rate based on three-month LIBOR plus 1.45% - 2.85% due 2034 to 2035 \| Maximum \| LIBOR
Short Term Borrowings and Long Term Debt [Line Items]
Basis spread on variable rate	2.85%
Subordinated Debt Obligations \| Subordinated debt obligations: floating-rate based on three-month LIBOR plus 3.25% due in 2032
Short Term Borrowings and Long Term Debt [Line Items]
Long-term borrowings, Amount	$ 4,255		$ 0
Long-term borrowings, Weighted Average Rate	4.25%		0.00%
Purchase accounting discounts	$ 700
Advances payable	$ 5,000
Subordinated Debt Obligations \| Subordinated debt obligations: floating-rate based on three-month LIBOR plus 3.25% due in 2032 \| LIBOR
Short Term Borrowings and Long Term Debt [Line Items]
Basis spread on variable rate	3.25%
Federal Home Loan Bank Advances \| FHLB advances: 0.60% - 0.66% fixed-rate notes
Short Term Borrowings and Long Term Debt [Line Items]
Short-term borrowings, Amount	$ 825,000		$ 100,000
Weighted average interest rate	0.65%		0.34%