Financial Information for Subsidiary Guarantors and Non-guarantor Subsidiaries (Condensed Consolidating Statements of Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Operating activities:
Net income (loss)	$ 27.0	$ (7.5)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	(0.1)	0.4
Depreciation and amortization	133.4	128.4
Amortization of loan costs	4.4	3.2
Accretion of principal on notes	2.2	5.2
Acquisition related expenses	0.1	12.6
Stock compensation	4.9	4.6
Deferred income taxes	7.0	(5.9)
Debt extinguishment costs	0	38.9
Other	1.2	(1.1)
Changes in operating assets and liabilities net of the effect of acquisitions	(92.9)	(172.2)
Net cash provided by (used in) operating activities — continuing operations	87.2	6.6
Net cash used in operating activities — discontinued operations	0.1	(0.4)
Net cash provided by (used in) operating activities	87.3	6.2
Investing activities:
Acquisitions and related expenses, net of cash acquired	(7.2)	(208.8)
Capital expenditures	(187.2)	(137.2)
Net proceeds from sales of investments in securities	(3.0)	11.9
Net reimbursements from restricted cash and escrow fund	17.8	0
Other investing activities	1.3	(0.7)
Net cash used in investing activities	(178.3)	(334.8)
Financing activities:
Payments of long-term debt and capital lease obligations	(5.5)	(460.7)
Proceeds from issuance of common stock	0	67.5
Payments of IPO related costs	0	(6.9)
Payments of tender premiums on note redemption	0	(27.6)
Cash provided by (used in) intercompany activity	0	0
Other financing activities	(1.2)	(1.6)
Net cash provided by (used in) financing activities	(6.7)	(429.3)
Net increase (decrease) in cash and cash equivalents	(97.7)	(757.9)
Cash and cash equivalents, beginning of period	455.5	936.6
Cash and cash equivalents, end of period	357.8	178.7
Parent [Member]
Operating activities:
Net income (loss)	26.1	(6.0)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	0	0
Depreciation and amortization	0	0
Amortization of loan costs	0	0
Accretion of principal on notes	0	0
Acquisition related expenses	0	0
Stock compensation	4.9	4.6
Deferred income taxes	7.0	(5.9)
Debt extinguishment costs		0
Other	0	0
Changes in operating assets and liabilities net of the effect of acquisitions	(38.0)	7.3
Net cash provided by (used in) operating activities — continuing operations	0	0
Net cash used in operating activities — discontinued operations	0	0
Net cash provided by (used in) operating activities	0	0
Investing activities:
Acquisitions and related expenses, net of cash acquired	0	0
Capital expenditures	0	0
Net proceeds from sales of investments in securities	0	0
Net reimbursements from restricted cash and escrow fund	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Financing activities:
Payments of long-term debt and capital lease obligations	0	0
Proceeds from issuance of common stock		67.5
Payments of IPO related costs		(6.9)
Payments of tender premiums on note redemption		0
Cash provided by (used in) intercompany activity	1.2	(60.2)
Other financing activities	(1.2)	(0.4)
Net cash provided by (used in) financing activities	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Issuers of Senior Notes and Term Debt [Member]
Operating activities:
Net income (loss)	(102.8)	(86.3)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	0	0
Depreciation and amortization	0	0
Amortization of loan costs	4.4	3.2
Accretion of principal on notes	1.7	1.4
Acquisition related expenses	0	0
Stock compensation	0	0
Deferred income taxes	0	0
Debt extinguishment costs		0
Other	0	0
Changes in operating assets and liabilities net of the effect of acquisitions	0.1	10.6
Net cash provided by (used in) operating activities — continuing operations	(96.6)	(71.1)
Net cash used in operating activities — discontinued operations	0	0
Net cash provided by (used in) operating activities	(96.6)	(71.1)
Investing activities:
Acquisitions and related expenses, net of cash acquired	0	0
Capital expenditures	0	0
Net proceeds from sales of investments in securities	0	0
Net reimbursements from restricted cash and escrow fund	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Financing activities:
Payments of long-term debt and capital lease obligations	(4.1)	(8.2)
Proceeds from issuance of common stock		0
Payments of IPO related costs		0
Payments of tender premiums on note redemption		0
Cash provided by (used in) intercompany activity	100.9	79.3
Other financing activities	(0.2)	0
Net cash provided by (used in) financing activities	96.6	71.1
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Issuers of Senior Discount Notes [Member]
Operating activities:
Net income (loss)	(0.6)	(42.7)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	0	0
Depreciation and amortization	0	0
Amortization of loan costs	0	0
Accretion of principal on notes	0.5	3.8
Acquisition related expenses	0	0
Stock compensation	0	0
Deferred income taxes	0	0
Debt extinguishment costs		38.9
Other	0	0
Changes in operating assets and liabilities net of the effect of acquisitions	0	0
Net cash provided by (used in) operating activities — continuing operations	(0.1)	0
Net cash used in operating activities — discontinued operations	0	0
Net cash provided by (used in) operating activities	(0.1)	0
Investing activities:
Acquisitions and related expenses, net of cash acquired	0	0
Capital expenditures	0	0
Net proceeds from sales of investments in securities	0	0
Net reimbursements from restricted cash and escrow fund	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Financing activities:
Payments of long-term debt and capital lease obligations	0	(445.8)
Proceeds from issuance of common stock		0
Payments of IPO related costs		0
Payments of tender premiums on note redemption		(27.6)
Cash provided by (used in) intercompany activity	0.1	473.4
Other financing activities	0	0
Net cash provided by (used in) financing activities	0.1	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	0	0
Guarantor Subsidiaries [Member]
Operating activities:
Net income (loss)	158.6	100.3
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	(0.1)	0.4
Depreciation and amortization	112.4	113.3
Amortization of loan costs	0	0
Accretion of principal on notes	0	0
Acquisition related expenses	0.1	8.0
Stock compensation	0	0
Deferred income taxes	0	0
Debt extinguishment costs		0
Other	1.2	(1.1)
Changes in operating assets and liabilities net of the effect of acquisitions	(52.3)	(167.7)
Net cash provided by (used in) operating activities — continuing operations	219.9	53.2
Net cash used in operating activities — discontinued operations	0.1	(0.4)
Net cash provided by (used in) operating activities	220.0	52.8
Investing activities:
Acquisitions and related expenses, net of cash acquired	(6.9)	(209.9)
Capital expenditures	(178.4)	(132.0)
Net proceeds from sales of investments in securities	0	1.9
Net reimbursements from restricted cash and escrow fund	17.8
Other investing activities	1.3	2.3
Net cash used in investing activities	(166.2)	(337.7)
Financing activities:
Payments of long-term debt and capital lease obligations	0.1	(6.6)
Proceeds from issuance of common stock		0
Payments of IPO related costs		0
Payments of tender premiums on note redemption		0
Cash provided by (used in) intercompany activity	(83.5)	(301.2)
Other financing activities	0	0
Net cash provided by (used in) financing activities	(83.4)	(307.8)
Net increase (decrease) in cash and cash equivalents	(29.6)	(592.7)
Cash and cash equivalents, beginning of period	305.8	644.1
Cash and cash equivalents, end of period	276.2	51.4
Combined Non-Guarantors [Member]
Operating activities:
Net income (loss)	(17.6)	31.7
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	0	0
Depreciation and amortization	21.0	15.1
Amortization of loan costs	0	0
Accretion of principal on notes	0	0
Acquisition related expenses	0	4.6
Stock compensation	0	0
Deferred income taxes	0	0
Debt extinguishment costs		0
Other	0	0
Changes in operating assets and liabilities net of the effect of acquisitions	(46.0)	(15.4)
Net cash provided by (used in) operating activities — continuing operations	(42.6)	36.0
Net cash used in operating activities — discontinued operations	0	0
Net cash provided by (used in) operating activities	(42.6)	36.0
Investing activities:
Acquisitions and related expenses, net of cash acquired	(0.3)	1.1
Capital expenditures	(8.8)	(5.2)
Net proceeds from sales of investments in securities	(3.0)	10.0
Net reimbursements from restricted cash and escrow fund	0
Other investing activities	0	(3.0)
Net cash used in investing activities	(12.1)	2.9
Financing activities:
Payments of long-term debt and capital lease obligations	(1.5)	(0.1)
Proceeds from issuance of common stock		0
Payments of IPO related costs		0
Payments of tender premiums on note redemption		0
Cash provided by (used in) intercompany activity	(12.1)	(201.0)
Other financing activities	0.2	(3.0)
Net cash provided by (used in) financing activities	(13.4)	(204.1)
Net increase (decrease) in cash and cash equivalents	(68.1)	(165.2)
Cash and cash equivalents, beginning of period	149.7	292.5
Cash and cash equivalents, end of period	81.6	127.3
Eliminations [Member]
Operating activities:
Net income (loss)	(36.7)	(4.5)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Income (loss) from discontinued operations, net of taxes	0	0
Depreciation and amortization	0	0
Amortization of loan costs	0	0
Accretion of principal on notes	0	0
Acquisition related expenses	0	0
Stock compensation	0	0
Deferred income taxes	0	0
Debt extinguishment costs		0
Other	0	0
Changes in operating assets and liabilities net of the effect of acquisitions	43.3	(7.0)
Net cash provided by (used in) operating activities — continuing operations	6.6	(11.5)
Net cash used in operating activities — discontinued operations	0	0
Net cash provided by (used in) operating activities	6.6	(11.5)
Investing activities:
Acquisitions and related expenses, net of cash acquired	0	0
Capital expenditures	0	0
Net proceeds from sales of investments in securities	0	0
Net reimbursements from restricted cash and escrow fund	0
Other investing activities	0	0
Net cash used in investing activities	0	0
Financing activities:
Payments of long-term debt and capital lease obligations	0	0
Proceeds from issuance of common stock		0
Payments of IPO related costs		0
Payments of tender premiums on note redemption		0
Cash provided by (used in) intercompany activity	(6.6)	9.7
Other financing activities	0	1.8
Net cash provided by (used in) financing activities	(6.6)	11.5
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents, beginning of period	0	0
Cash and cash equivalents, end of period	$ 0	$ 0