CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Allowances for accounts receivable, current	$ 96,164	$ 93,267
Shareholders' equity of Frontier:
Common stock, par value (in dollars per share)	$ 0.25	$ 0.25
Common stock, shares authorized (in shares)	1,750,000,000	1,750,000,000
Common stock, shares outstanding (in shares)	998,131,000	998,410,000
Common stock, shares issued (in shares)	1,027,986,000	1,027,986,000