Premises and Equipment - Summary of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Premises and Equipment [Line Items]
Total Cost	$ 206,863	$ 175,430
Accumulated Depreciation and Amortization	(109,215)	(97,739)
Net	97,648	77,691
Land
Premises and Equipment [Line Items]
Total Cost	26,510	19,373
Buildings and Leasehold Improvements
Premises and Equipment [Line Items]
Total Cost	115,461	99,451
Equipment
Premises and Equipment [Line Items]
Total Cost	$ 64,892	$ 56,606