CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net income	$ 50,783	$ 30,490
Other comprehensive income, net of tax (see Note 15)	6,746	4,267
Comprehensive income	57,529	34,757
Less: Net income attributable to the noncontrolling interest in a partnership	(2,643)	(3,722)
Comprehensive income attributable to the common shareholders of Frontier	$ 54,886	$ 31,035

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

+ References+ Details

- Definition

Amount of net Income or Loss for the period allocated to noncontrolling partners of a limited partnership included in the entity's consolidated financial statements.

+ References+ Details