Fair Value Measurements Fair Value Inputs, Quantitative Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Loans and Leases Receivable, Impaired Loans | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(0.00%)
Loans and Leases Receivable, Impaired Loans | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(66.00%)
Loans and Leases Receivable, Impaired Loans | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(31.00%)
Real Estate Acquired in Satisfaction of Debt | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(8.00%)
Real Estate Acquired in Satisfaction of Debt | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(96.00%)
Real Estate Acquired in Satisfaction of Debt | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(18.00%)
Asses to be Disposed of by Sale | Minimum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(0.00%)
Asses to be Disposed of by Sale | Maximum | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(9.00%)
Asses to be Disposed of by Sale | Weighted Average | Market Approach Valuation Technique
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate	(6.00%)
Carrying Amount
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	$ 5,300,311	$ 5,340,536
Change During Period | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Long-lived assets to be disposed of by sale	209	1,028
Estimated Fair Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	5,148,977	5,248,127
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	37,484	39,344
Long-lived assets to be disposed of by sale	356	1,335
Other real estate owned	1,682	2,110
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans		39,344
Long-lived assets to be disposed of by sale	356	1,335
Other real estate owned	1,682	2,110
Significant Unobservable Inputs (Level 3) | Carrying Amount | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	63,304	65,238
Long-lived assets to be disposed of by sale	565	2,363
Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Loans Receivable, Fair Value Disclosure	37,484	39,344
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	$ 37,484	$ 39,344