Intangible Assets (Loan Servicing Rights at Fair Value) (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)
Activity for Loan Servicing Rights Accounted for Under Fair Value Method
Fair value, beginning of period	$ 0	$ 0
Acquired in Talmer Bancorp, Inc. merger	42,462	42,462
Additions from loans sold with servicing retained	810	810
Reductions from pay-offs, pay downs and run-off	(687)	(687)
Changes in estimates of fair value	(657)	(657)
Fair value, end of period	41,928	41,928
Principal balance of loans serviced	5,602,828	5,602,828
Commercial Real Estate [Member]
Activity for Loan Servicing Rights Accounted for Under Fair Value Method
Fair value, beginning of period	0	0
Acquired in Talmer Bancorp, Inc. merger	365	365
Additions from loans sold with servicing retained	0	0
Reductions from pay-offs, pay downs and run-off	(2)	(2)
Changes in estimates of fair value	0	0
Fair value, end of period	363	363
Principal balance of loans serviced	79,405	79,405
Mortgage [Member]
Activity for Loan Servicing Rights Accounted for Under Fair Value Method
Fair value, beginning of period	0	0
Acquired in Talmer Bancorp, Inc. merger	42,097	42,097
Additions from loans sold with servicing retained	810	810
Reductions from pay-offs, pay downs and run-off	(685)	(685)
Changes in estimates of fair value	(657)	(657)
Fair value, end of period	41,565	41,565
Principal balance of loans serviced	$ 5,523,423	$ 5,523,423