Statements of Condition (Unaudited) Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
ASSETS
Held-to-maturity Securities, Fair Value	$ 5,209,238	$ 5,283,965
Loans and Leases Receivable, Allowance	$ 175	$ 183
CAPITAL
Common Stock, Par or Stated Value Per Share	$ 100	$ 100
Common Stock, Shares, Issued	11,401,713	12,169,858
Common Stock, Shares, Outstanding	11,401,713	12,169,858