Goodwill and Other Intangible Assets - Summary of Changes in Carrying Amount of Goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 172,559
Goodwill, Acquired During Period	0
Goodwill, Ending Balance	172,559
Banking [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	138,476
Goodwill, Acquired During Period	0
Goodwill, Ending Balance	138,476
Wealth Management [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	15,434
Goodwill, Acquired During Period	0
Goodwill, Ending Balance	15,434
Insurance [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	18,649
Goodwill, Acquired During Period	0
Goodwill, Ending Balance	$ 18,649