Goodwill and Intangible Assets, Summary of Core Deposit and Other Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Summary of core deposit intangibles and other intangibles
Additions during the period		$ 1,000				$ 12,000
Amortization of other intangible assets	$ 525		$ 885	$ 1,568	$ 2,574
Core Deposit Intangibles [Member]
Summary of core deposit intangibles and other intangibles
Gross carrying amount	4,385			4,385		19,545
Accumulated amortization	(4,203)			(4,203)		(19,152)
Total Estimated Amortization Expense	182			182		393
Amortization of other intangible assets				211		1,404
Other Intangible Assets [Member]
Summary of core deposit intangibles and other intangibles
Gross carrying amount	32,410			32,410		31,398
Accumulated amortization	(16,690)			(16,690)		(15,333)
Total Estimated Amortization Expense	$ 15,720			15,720		16,065
Additions during the period				1,012		12,115
Amortization of other intangible assets				$ 1,357		$ 1,690