Shareholder's Equity (Narrative) (Details)						3 Months Ended		9 Months Ended
	Aug. 27, 2015 USD ($) $ / shares	May. 20, 2015 USD ($) $ / shares	Mar. 03, 2015 USD ($) $ / shares	Jul. 16, 2014 shares	Jul. 02, 2014 USD ($) $ / shares shares	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($) shares	Sep. 30, 2015 USD ($) installment $ / shares shares	Sep. 30, 2014 USD ($) $ / shares shares	Aug. 09, 2013 USD ($)
Common Stock:
Stock repurchased program authorized by the board of directors | $										$ 40,000,000.0
Mandatory Convertible Preferred Stock
Preferred stock dividends | $	$ (2,300,000)	$ (2,300,000)	$ (2,300,000)			$ (2,264,000)	$ (2,239,000)	$ (6,792,000)	$ (2,239,000)
Stock Incentive Plans:
Number of shares authorized for grant under share incentive plan						1,200,000		1,200,000
Shares available for future grants/issuance under stock incentive plan						893,347		893,347
Unrecognized compensation cost on non vested awards | $						$ 20,600,000		$ 20,600,000
Weighted average period								1 year 1 month 15 days
Number of units granted								313,498
Grant date value of common stock | $ / shares								$ 56.19
Stock Repurchased To Cover Employee Tax Withholdings [Member]
Common Stock:
Repurchase of common stock, shares								67,000	68,748
Repurchase of common stock | $								$ 3,700,000	$ 2,900,000
Stock Options [Member]
Stock Incentive Plans:
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period								4 years
Options term								10 years
Employees [Member] | Restricted Stock [Member]
Stock Incentive Plans:
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period								4 years
Number of installments in restricted stock granted. | installment								3
Mandatory Convertible Preferred Stock [Member]
Stock Incentive Plans:
Number of anti-dilutive options								3,100,000
Stock Options [Member]
Stock Incentive Plans:
Number of anti-dilutive options						0	0	0	0
Common Stock [Member]
Issuance of stock (in shares)					9,775,000
Issuance of stock, price per share | $ / shares					$ 45.00
Stock offering expenses | $					$ 18,500,000
Mandatory Convertible Preferred Stock [Member]
Issuance of stock (in shares)					1,725,000
Issuance of stock, price per share | $ / shares					$ 100.00
Stock offering expenses | $					$ 5,900,000
Mandatory Convertible Preferred Stock
Dividend rate								5.25%
Initial liquidation preference (usd per share) | $ / shares						$ 100		$ 100
Consecutive trading day								20 days
Dividends declared (usd per share) | $ / shares	$ 1.3125	$ 1.3125	$ 1.3125						$ 1.2979
Sheridan Healthcare [Member] | Common Stock [Member]
Common Stock:
Shares of common stock issued for acquisition				5,713,909
Minimum [Member] | Mandatory Convertible Preferred Stock [Member]
Mandatory Convertible Preferred Stock
Conversion rate						1.8141		1.8141
Maximum [Member] | Mandatory Convertible Preferred Stock [Member]
Mandatory Convertible Preferred Stock
Conversion rate						2.2222		2.2222
Performance-based Restricted Stock Units [Member]
Stock Incentive Plans:
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period								3 years
Number of units granted								68,533
Grant date value of common stock | $ / shares								$ 55.40
Performance goal period for vesting								1 year
Projected vesting percentage								150.00%
Performance-based Restricted Stock Units [Member] | Minimum [Member]
Stock Incentive Plans:
Projected vesting percentage								0.00%
Performance-based Restricted Stock Units [Member] | Maximum [Member]
Stock Incentive Plans:
Projected vesting percentage								150.00%