Completed securities trade of a shorted U.S. Treasury security.

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- Definition

Termination fees associated with pay-fixed interest rate swaps.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

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DERIVATIVE FINANCIAL INSTRUMENTS (FY) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2014	Sep. 30, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2013
Derivative financial instrument according to type of hedge[ Abstract]
Termination fee					$ 600
Completed securities trade	$ 13,000
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		$ 1,973	$ 2,251	$ 1,238
Liability Derivatives		1,073	975	619
No Hedge Designation [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount		$ 222,740	$ 187,092	$ 126,271
Average Maturity		3 years 6 months	4 years 4 months 24 days	3 years 8 months 12 days
Fair Value		$ 795	$ 1,276	$ 619
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		1,868	2,251
Liability Derivatives		1,073	975
No Hedge Designation [Member] \| Rate-Lock Mortgage Loan Commitments [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount		$ 36,580	$ 26,658	$ 20,581
Average Maturity		1 month 6 days	1 month 6 days	1 month 6 days
Fair Value		$ 769	$ 646	$ 550
No Hedge Designation [Member] \| Mandatory Commitments to Sell Mortgage Loans [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount		$ 74,750	$ 61,954	$ 46,320
Average Maturity		1 month 6 days	1 month 6 days	1 month 6 days
Fair Value		$ 26	$ 630	$ 69
No Hedge Designation [Member] \| Purchased Options [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount		$ 3,119	$ 3,119	$ 2,098
Average Maturity		3 years 9 months 18 days	4 years 6 months	5 years 8 months 12 days
Fair Value		$ 277	$ 238	$ 122
No Hedge Designation [Member] \| Written Options [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount		$ 3,119	$ 3,119	$ 2,098
Average Maturity		3 years 9 months 18 days	4 years 6 months	5 years 8 months 12 days
Fair Value		$ (277)	$ (238)	$ (122)
Fixed Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount			$ 46,121	$ 27,587
Average Maturity			8 years 7 months 6 days	8 years
Fair Value			$ 249	$ (497)
Variable Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Derivative financial instrument according to type of hedge[ Abstract]
Notional Amount			$ 46,121	$ 27,587
Average Maturity			8 years 7 months 6 days	8 years
Fair Value			$ (249)	$ 497
Other Assets [Member] \| No Hedge Designation [Member] \| Rate-Lock Mortgage Loan Commitments [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		769	646	550
Other Assets [Member] \| No Hedge Designation [Member] \| Mandatory Commitments to Sell Mortgage Loans [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		26	630	69
Other Assets [Member] \| No Hedge Designation [Member] \| Purchased Options [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		277	238	122
Other Assets [Member] \| No Hedge Designation [Member] \| Written Options [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives		0	0	0
Other Assets [Member] \| Fixed Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives			493	0
Other Assets [Member] \| Variable Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Asset Derivatives			244	497
Other Liabilities [Member] \| No Hedge Designation [Member] \| Rate-Lock Mortgage Loan Commitments [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives		0	0	0
Other Liabilities [Member] \| No Hedge Designation [Member] \| Mandatory Commitments to Sell Mortgage Loans [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives		0	0	0
Other Liabilities [Member] \| No Hedge Designation [Member] \| Purchased Options [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives		0	0	0
Other Liabilities [Member] \| No Hedge Designation [Member] \| Written Options [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives		$ 277	238	122
Other Liabilities [Member] \| Fixed Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives			244	497
Other Liabilities [Member] \| Variable Income Interest Rate [Member] \| No Hedge Designation [Member] \| Interest Rate Swap [Member]
Fair value of derivative instruments, balance sheet location [Abstract]
Liability Derivatives			$ 493	$ 0