Fair Value - Fair Value Measurements for Items Measured at Fair Value (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale		$ 23,998	$ 12,078
Other real estate owned		7,039	7,462
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	[1]	790,766	741,375
Loans held for sale	[2]	23,998	12,078
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	[1]	225	3,899
Loans held for sale	[2]	0	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	[1]	790,541	737,476
Loans held for sale	[2]	23,998	12,078
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	[1]	0	0
Loans held for sale	[2]	0	0
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	[3]	7,511	10,409
Other real estate owned	[4]	7,039	7,462
Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	[3]	0	0
Other real estate owned	[4]	0	0
Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	[3]	6,052	8,324
Other real estate owned	[4]	598	1,468
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	[3]	1,459	2,085
Other real estate owned	[4]	$ 6,441	$ 5,994

[1] See Note D for further detail of fair value of individual investment categories.

[2] Recurring fair value basis determined using observable market data.

[3] See Note F. Nonrecurring fair value adjustments to loans identified as impaired reflect full or partial write-downs that are based on the loan’s observable market price or current appraised value of the collateral in accordance with ASC 310.

[4] Fair value is measured on a nonrecurring basis in accordance with ASC 360.