Disclosures About Fair Value of Financial Instruments - Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial assets:
Available-for-sale securities	$ 280,560	$ 276,021
Level 1 [Member]
Financial assets:
Available-for-sale securities	113,355	74,974
Level 2 [Member]
Financial assets:
Available-for-sale securities	167,205	201,047
Recurring [Member]
Financial assets:
Available-for-sale securities	280,560	276,021
Recurring [Member] | Interest Rate Swap
Financial assets:
Derivative asset	3,692	1,528
Financial Liabilities:
Derivative liability	3,909	1,612
Recurring [Member] | Interest Rate Cap
Financial assets:
Derivative asset	1	25
Financial Liabilities:
Derivative liability	1	25
Recurring [Member] | Level 1 [Member]
Financial assets:
Available-for-sale securities	113,355	74,974
Recurring [Member] | Level 2 [Member]
Financial assets:
Available-for-sale securities	167,205	201,047
Recurring [Member] | Level 2 [Member] | Interest Rate Swap
Financial assets:
Derivative asset	3,692	1,528
Financial Liabilities:
Derivative liability	3,909	1,612
Recurring [Member] | Level 2 [Member] | Interest Rate Cap
Financial assets:
Derivative asset	1	25
Financial Liabilities:
Derivative liability	$ 1	$ 25