Goodwill and Other Intangible Assets (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 469,433,000	$ 469,433,000	$ 469,433,000
Number of operating segments | segment	3
Goodwill impairment			$ 0
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 1,817,000	2,104,000
Core Deposit Intangibles
Finite-Lived Intangible Assets [Line Items]
Impairment write-downs	0	0
Amortization expense	$ 1,800,000	$ 2,100,000